February 12, 2026 • 46 mins
It turns out that lasers are even cooler than they look. And as far as acronyms go, they’re pretty solid in that respect too. There’s way too much cool stuff about lasers to tease here so listen to this old school SYSK episode and let lasers blow away.
See omnystudio.com/listener for privacy information.
Mark as Played
Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:01):
Welcome to Stuff you should know, a production of IHEARTRADIOW.
Speaker 2 (00:11):
And welcome to the podcast. I'm Josh, and there's Chuck
and Jerry's here too. And she was making too many
laser noises, so we asked her to please go on
you because she did, and I assume she's still making
laser noises. We just can't hear right now.
Speaker 1 (00:25):
You have a little attitude about it.
Speaker 2 (00:26):
Too, she did. I mean, I was really mean and kurt,
but she didn't have to be that way back.
Speaker 1 (00:33):
Yeah, this is a one way street, right, it's.
Speaker 2 (00:37):
My way or the highway.
Speaker 1 (00:40):
You know, it's about time we did an episode on lasers.
This seems like something that we would have tackled in
those first formative in that first formative decade, and.
Speaker 2 (00:51):
I'm glad we didn't because I think it's good to
still do like a traditional you know, how X works episode,
we should do one, And how X works it depends
on what kind of X you're talking about.
Speaker 1 (01:05):
Ruby used to give us an X when she was little,
when she was like two years old. If she didn't
like something, she would do her fingers as an X.
Speaker 2 (01:13):
And she just keeps getting cooler and cooler.
Speaker 1 (01:15):
She forgot that she lost that one along the way.
I told her to bring that back.
Speaker 2 (01:19):
Yeah, that's a good one.
Speaker 1 (01:19):
Uncle Josh likes it.
Speaker 2 (01:21):
That's like talk to the hand, but way better.
Speaker 1 (01:23):
Yeah, exactly.
Speaker 2 (01:26):
All right, So we're talking lasers today, not necessarily X.
Maybe we will do X someday. Let's find out, okay,
And everybody knows what a laser is, right.
Speaker 1 (01:36):
Yeah, I mean I feel like it's one of the
more like one of those acronyms like scuba that you
learn when you're like on the playground. M hm. So
in this case, it stands for light amplification by stimulated
emission of radiation. And now that I know what a
laser is and how it works, they kind of nailed
it with that acronym they did.
Speaker 2 (01:58):
You you can totally forgive them for the B and
the of because that's a world class acronym.
Speaker 1 (02:03):
Yeah, that would be lab sere if they included those
lasers so much cooler.
Speaker 2 (02:12):
Lab se or doesn't. It doesn't have that same ring
to it as laser.
Speaker 1 (02:15):
Throw me the lab se or gun.
Speaker 2 (02:18):
That someone would say. No. So, lasers are everywhere everybody,
They're all around you. A lot of them are pointed
at you right now, you just can't see them. But
like a UPC code scanner at a supermarket checkout. They
still have supermarkets, right, Oh yeah, that's right. Everyone goes
in and empties all of their bank accounts into them
(02:40):
every week to get suesstenates. Well, when you check out,
boo boo boop like that, that's actually a laser being triggered.
You're scanning your UPC code. So lasers are everywhere. They're
at the supermarket. At least, that doesn't necessarily mean you
understand them. I didn't understand them until we started to
research this, did you know.
Speaker 1 (03:01):
And it's really not that hard to wrap your head around.
Actually I was kind of dreading this. But Dave did
a great job with this article, sort of like you
here in the traditional sense, like you said, yep, And
he does a good job initially by sort of laying
the groundwork of regular light compared to a laser light.
And I think that's a great way to start.
Speaker 2 (03:21):
Well, yeah, if we're going to talk about lasers, we
really I mean, we're talking about light. We kind of
need to go back a couple of steps and say, okay,
there's different kinds of light, you know, like the light
we think of as sunlight or a light bulb or
something like that, what we would call generally white light
is as a lot of people know, all of the
colors of the spectrum, the visible light spectrum together coming
(03:43):
together to form white light.
Speaker 1 (03:46):
That's right, many different wavelengths. But just like you know,
elementary school science, when you get that prism and your
little mind is blown, it's still kind of blows my mind.
You scatter that light into its different wavelengths and it's
the colors of the rainbow there. But and this is
something that like I don't think I even realize this,
even those different wavelengths, it's not a single wavelengths. It's
(04:09):
still a spectrum of different wavelengths creating the red or
the blue or the yellow or whatever. And that's kind
of where we find ourselves, you know, departing in what
a laser ends at being.
Speaker 2 (04:24):
Yeah, because so for example, the yellow band, what we
see is yellow, and the visible spectrum occupies the five
hundred and seventy nanimeter to five hundred and ninety nanimeter range.
You show up below that, I think you've got what
red orange, something like that. ROYGBIV, Yeah, I can't remember
above that you've got blue Green, roy g Green, and
(04:46):
those just have different wave links. They're all electromagnetic light.
It's the same thing as a microwave. It's the same
thing as a radio wave. It's the same thing as
a gamma ray. It's just the different frequencies make them
different kinds of energy what we call the visible spectrum.
The point is is within all those different nanometer wavelengths,
(05:07):
say from five to seventy to five ninety, there's different
kinds of yellow. There's different shades of yellow right in
there across that the spectrum within the spectrum, I guess.
Speaker 1 (05:16):
Yeah, spectrum within the spectrum. Also a great album title.
Speaker 2 (05:21):
That is a great album title, Jeszisch. Maybe you could
have like a prism with a beam of light coming
in and then a rainbow coming out the other side.
Speaker 1 (05:29):
Yeah, this is nineteen sixties for sure.
Speaker 2 (05:31):
Yeah, pyramid even is a prism.
Speaker 1 (05:34):
Yeah. With Isaac Kay's's head floating above it.
Speaker 2 (05:38):
I'm describing the Dark Side of the Moon album cover.
Speaker 1 (05:42):
I know it's just kidding.
Speaker 2 (05:43):
Okay, well you were really throwing me off, you were.
That was some meta joking right there.
Speaker 1 (05:47):
I have a great pressing of Dark Side of the
Moon by the way you do. Yeah, you know, I
had a record press or a guy who does that
for a living. I was hanging out with him in
New York with our friend Joey Ciara and these two
guys who did that, and he said, yeah, some pressings
like it's done by a human, so you might have
some records that just sound really awesome because it was
well done. And I was like yeah, and they're you know,
(06:08):
one hundred and eighty gram. He was like, that's all bunk,
by the way. He's like, it just makes you feel
better that it's heavier, and I was like, oh man,
that's disappointing.
Speaker 2 (06:17):
I do like the heft of a eighty gram.
Speaker 1 (06:19):
Apparently, they said, is that's all just for you to
make you think it is better because it's heavier.
Speaker 2 (06:25):
It's heavier, so it's worth more.
Speaker 1 (06:26):
All right. So back to lasers. What you just described
very well, by the way, was regular light wavelength within
the wavelength. If you talk about the differences of a
laser light, you're talking about three main differences, in the
first of which is that single wavelength it's monoc like
truly monochromatic. That beam of light that a laser is
(06:47):
or I guess you know, produces Well, no, it's what
it is is is just a very it's a single wavelength,
highly highly concentrated.
Speaker 2 (06:56):
Yeah, so rather than say a wavelength between five seventy
and five for being yellow, this is a five hundred
and seventy two nanometer wavelength that is that specific yellow.
That's right, and it's it's not it's made up entirely
of yellow light on the exact same wavelength. That is
incredibly important. That's a huge, huge difference. Lasers don't occur naturally.
(07:19):
We've figured out how to make them, and by we,
I'm including myself in you.
Speaker 1 (07:24):
That's right. The second big difference between laser light and
regular light is that it's coherent. So not only is
it just a single wavelength, but the photons of the light,
and we're going to talk about where they come into
play here in a second. Thanks to mister Einstein or
doctor Einstein, the photons are perfectly in phase with one another.
So if you look at that wavelength, the peaks and
(07:46):
the troughs are all perfectly in sync.
Speaker 2 (07:49):
Yeah, and not like they're following the same plane and
they're just kind of in synct like that like, they're
upright above each other, right below each other. They're not
interfering with one another in any way whatsoever.
Speaker 1 (08:00):
That's right.
Speaker 2 (08:01):
And then the last one is that they're colimated, meaning
they're all traveling in the exact same direction.
Speaker 1 (08:07):
Yeah, I mean that's important. I mean culimated sort of
a fancy way of saying directional. But as we'll see,
they all have to be traveling that same direction to
pick up their little photon buddies.
Speaker 2 (08:18):
Yeah. So essentially what you've got is a very specific
kind of the exact same kind of light, none of
which are interfering with the other photons that are coming
out of the laser, all of which are traveling in
the same direction, so they do not get in one
another's way, and they can be combined very very tightly.
And that's essentially what a laser does.
Speaker 1 (08:38):
Yeah, for sure. And it all goes back to that
acronym stimulated emission, the SE and laser. You can't make
a laser without SE, that's true. You can't spell laser
without SE, and you can't have a laser without stimulated emission.
And our buddy Einstein is the guy who sort of
laid the theoretical groundwork. He didn't go out and build
(08:59):
a laser. That came later, but he laid the theoretical
groundwork for all of this back in the ridiculously in
the early nineteen hundreds.
Speaker 2 (09:08):
Yeah, so back in nineteen oh five, most people were like,
light's a continuous wave, and by proxy, the universe is
one smooth, continuous thing. In Einstein's like, I don't think
that's true. I think if you zoom in far enough,
close enough into the fabric of the universe, you're going
to see it's actually made of discrete, little little things
(09:28):
and call them pixels, right, And he's like, if that's true,
then light can't be one continuous wave either. So I
think they're actually made up of those little tiny packets
that I'm going to call photons. And he turned out
to be right. He had a great equation for it too.
It's so elegantly simple. That's the thing about Einstein. He
(09:49):
could come up with like three different things and could
completely change our understanding of the universe.
Speaker 1 (09:54):
Yeah, for sure, this is the Planck Einstein, Einstein, what
just happened? I was concentrating so heavily. I'm not saying Plank.
Speaker 2 (10:03):
I've heard Plank I think that's how most people say.
Speaker 1 (10:05):
Oh, I've always heard plank.
Speaker 2 (10:07):
Okay, I've heard both, but most of the people I've
ever heard say plank. But I mean, I run in
pretty low brow crowds.
Speaker 1 (10:14):
I think the probably the correctest plank, but most people
do say plank. You're right.
Speaker 2 (10:18):
I like the way that you said it the first time.
The plank Einstein.
Speaker 1 (10:21):
No, it says Einstein though. Yeah, the Plank Einstein relation,
which is the energy beach photon is equal to its
frequency times Plunk's constant e equals HF.
Speaker 2 (10:36):
Yeah, and all Plunk's constant is all it is. It's
the smallest possible measurement of energy that anything can have
on like the quantum level. Right, And so Einstein was like, Hey,
I want to figure out how all this stuff kind
of interacts because I know that photons interact with electrons.
I'm just positive of it.
Speaker 1 (10:56):
Wow.
Speaker 2 (10:57):
And they were figured that's pretty good. They were figuring out.
He was figuring out I think other people were at
the same time that when you have sub atomic particles
like an electron orbiting an atom, which if you go
listen to our periodic Table episode, I think we did
a pretty decent explanation of how you know that symbolism
(11:18):
or that visualization of it is not very correct. But
for all intents and purposes for this, let's say that
these electrons orbit in different orbits around the atom, and
when a photon hits it that orbit, that electron goes
up in energy I think for like one hundred nanoseconds typically, Yeah,
and then it says, okay, I want to get back
(11:39):
to my resting state it's ground state, and it goes
back to its previous orbital But when it does, it
poops out a photon.
Speaker 1 (11:45):
You know what's funny? What as earlier when I was
going over there in my head, I said, poops out
of photon.
Speaker 2 (11:50):
Sure, I mean you and I we share a brain
when it comes to toilet humor.
Speaker 1 (11:55):
Yeah, that's true. Yeah, that's exactly right. So an atom
is going to absorb that energy, and it can do
that in a lot of ways, but let's just say
in this case, it's like some it gets heated up,
you know, like literally heated up. Those electrons are going
to jump around and get excited. But once they that
makes it unstable. But it wants to be stable. So
when it goes back to that state. You're right, it
poops out that photon. Einstein saw this, called it spontaneous emission. Yeah,
(12:22):
and this happens all the time all over the place
in nature. These photons are getting pooped out all over
the place. But Einstein was like, well, hey, if it
happens all the time naturally, he theorized, maybe we can
we can stimulate it to do this. Maybe we can
make this happen and control that emission.
Speaker 2 (12:40):
Yeah, Because here's the thing, right, Like you say you
have a photon that hits an atom and knocks an
electron into the higher energy state, then that electron poops
out a photon. Well, that electron is just absorbed the photon.
So another way of looking at it is the photon
essentially goes into the electron and comes back out the
other side kind of, but there's only one photon ever,
(13:02):
one gets absorbed, one's produced. What Einstein figured out is
with stimulated emission, you can use a photon to create
another photon without losing the first photon. And if you
do that a bunch of times, buddy, you can have like, oh,
like you could make a basket with your shirt and
fill it with photons.
Speaker 1 (13:20):
If you do it, right, Yeah, I mean he realized
that photons like to hang out with one another, so
it doesn't take a lot to get them, you know,
traveling in a direction and saying, hey, buddy, come with me,
and it creates this sort of sort of like a snowball,
like a cascading effect where if you can get them
in an excited state and stimulate them and have them
(13:44):
pick up other photons and have them all travel in
the same direction, you're like halfway toward laser town pretty much.
Speaker 2 (13:53):
You can see the outskirts of town and the light
shooting up in the sky.
Speaker 1 (13:56):
Yeah you can.
Speaker 2 (13:58):
So yeah, So that's stimulated emission. And the key here
is you don't have to spend a photon to get
a photon, right, You can excite the atom in other
ways as long as it's already in its excited state.
When the photon comes along, it's going to produce another photon. Now,
for the purposes of lasers, what's really really important here
(14:18):
is it is going to produce an exactly identical photon
as the first one that passes by, right, traveling in
the same direction, and it's not going to interfere with
the first one. So they're cohesive, and they're collimated, and
they're exactly the same. They're monochromatic, which, as we said before,
those are the things you need for a laser. So
(14:39):
Einstein figured out back in nineteen seventeen how to make
a laser, and it was like, you, guys, figure it out.
I'm going to think about some other stuff.
Speaker 1 (14:47):
Yeah. And if you say, well, wait a minute, I
thought you said nineteen oh five, like it even took
Ein Einstein a little while to get there, you know,
that's right, took a little while. So should we take
a break.
Speaker 2 (14:58):
Yeah, I feel like a break is imminent.
Speaker 1 (15:00):
We'll be right back with more lasers, all right. So
(15:24):
when we left, Einstein did some great work kind of
laying the groundwork, this theoretical foundation of a laser. And
then he was like, guys, I like to think of
things with my brain and say them out loud and
write them on chalkboards. If you want to build this thing, fine,
maybe slide me some cash. But I don't do that
(15:45):
kind of work. So people did though, that followed in
his footsteps, and in the nineteenth fifties it was a
physicist named Charles Towns. He worked at Bell Labs and
he was doing research on microwaves microwave radiation, and he
was trying to He didn't know it yet, but he was.
He was halfway to laser town because he was trying
(16:06):
to find ways to concentrate a beam of microwaves.
Speaker 2 (16:10):
In this case, what's nuts is this guy figured it out.
He just basically tinkered around and made his own version
of a laser. But rather than using light, he used
microwave beams. Right.
Speaker 1 (16:22):
Yeah, he built like a thing.
Speaker 2 (16:24):
Yeah, he just he used ammonia adams. He put him
in a sealed chamber and he got them to essentially
emit microwave radiation that he was able to concentrate into
a beam. Right, So that cascading effect happened just like
we discussed before, and essentially the only difference is it
wasn't a light, it was a microwave beam. And to
(16:47):
test it, he aimed it at the front pocket of
a passing colleague, Percy Spencer, who happened to have a
chocolate bar in the front pocket, and he melted it and
Percy Spencer never forgave him because that was his favorite
short sleeve, button down shirt.
Speaker 1 (17:04):
I think we talked about this, did we do one
of microwaves. Yeah, okay, well that would be exactly where
we talked about it then, probably.
Speaker 2 (17:10):
Yeah, and they weren't colleagues. I just made that part up.
But that was a that was for you, buddy.
Speaker 1 (17:15):
Oh no, wait, there was a chocolate thing though, what right?
Speaker 2 (17:18):
Yeah, yeah, yeah, that happened. But separately, I think Spencer
was in the presence of some microwave generator and his
chocolate bar melted. And now that went on to invent microwaves.
This thing was totally different. It's just yeah, it just
brought Percy Spencer to mind.
Speaker 1 (17:31):
Yeah, I like it. So he literally called this a mazer,
a microwave amplified stimulated emission of radiation. He teamed up
with a guy. It was a colleague named Arthur Shallow,
and he said, let me see if we can do
the same thing with light, and we'll call it an
optical maser. And everyone was like, buddy, it's right there
(17:54):
in front of your face, like, come on, just get there.
Speaker 2 (17:59):
I think it was theor myman I like to call
him my man who actually came up with the laser.
He built the first functional laser in nineteen.
Speaker 1 (18:11):
Sixty and came up with a name.
Speaker 2 (18:13):
I think he did Okay. Up to this point, they
were all theoretical and my man was the first one
to actually build one, and he used a ruby crystal,
which at the time I think had already been dismissed.
People were like, you can't use that to make a laser.
And he's like, let me try again, and he did
some more calculations. He's like, the ruby's actually going to
(18:35):
be great. So he used a pink ruby crystal as
what's called the gain medium.
Speaker 1 (18:41):
Yeah, that's like the material lasing material that you would
use exactly.
Speaker 2 (18:45):
That's where the atoms that you get excited are all stored.
Speaker 1 (18:48):
Yeah, So he surrounded that crystal with a with a flash.
It was a coil shaped flash bulb. So that's that's
going to be the thing that you know, the heat
or whatever or the light that stimulates the initial reactions
the pump. Sure, and then the two ends of that
crystal were painted reflective silver. So everything is sort of
(19:10):
kind of trapped in there together, encouraging all those photons
to bounce around and get a little wild and create
more photons and say, hey, you know we're doing something here,
guys and all.
Speaker 2 (19:20):
Yeah, all of these photons came out at six hundred
and ninety four nanometers, which I guess is the precise
wavelength of ruby red.
Speaker 1 (19:26):
Yeah, I guess so.
Speaker 2 (19:28):
And he showed that like there, there, here's a laser.
Check it out. Let me see your face. Basically, I
think was how he showed it off right. He would
just wave it in people's faces.
Speaker 1 (19:37):
That's why he's my man.
Speaker 2 (19:40):
So that was it. I mean, that was the first
laser that and it was what you want to say,
like it was as easy as that. Of course that's
not easy, but the principle of it is kind of
like you said, it's simple to understand, which is great.
Like we did one on the breathalyzer, and it is
so ridiculously complicated. It's more complicated than a laser by far.
Speaker 1 (20:03):
I hated that one.
Speaker 2 (20:05):
I did too.
Speaker 1 (20:05):
That was a long period of time ago.
Speaker 2 (20:07):
I remember we picked it, we started researching, and I
was like.
Speaker 1 (20:10):
This sucks.
Speaker 2 (20:10):
Wait, why am I not understanding this? It was just
so complex. Let's never talk about it again.
Speaker 1 (20:16):
I think we just wanted the explanation to be like
blow into tube smells beer exactly.
Speaker 2 (20:22):
You just make a bunch of like drunk jokes.
Speaker 1 (20:24):
Exactly, all right, So that that was the first laser,
Like you said, he use that ruby to begin with.
But there are all sorts of gain mediums. There can
be liquids, there can be gases, and we should probably
go over the five main types of laser now, starting
with like if you've ever been for tattoo removal or
(20:45):
like had a skin cancer with laser removal, they're using
a solid state laser in that case, and it's called
solid state because they're using a solid crystal or a
glass or something like that. Mix it up with a
little with a gain medium like well, it's they're all
rare earth elements like chromium or something like that. Neodymium
(21:07):
is that one.
Speaker 2 (21:09):
Yeah, there's also a bitterum you abitterum man I even
looked it up, udbium atbium.
Speaker 1 (21:17):
Aterbium I betze, right, that's a that's why that looks funny.
Speaker 2 (21:20):
It is great though, why t t E r b
I U m yatterbium I got it And all of
those Basically they dope that say, like you could still
use ruby, but you would create like a ruby crystal
that's doped with these impurities that you've selected based on
their say like reflective properties, or they're phosphorescent properties. These
(21:42):
things can generate some photons really efficiently, and they're going
to generate them in exactly the wavelength that you want. Yeah,
it's a solid state laser. I follows in the tradition
of that original Mamayan's laser from nineteen sixty.
Speaker 1 (21:55):
You know, Emily knows not much about football, doesn't care,
but there's always a few plays that she knows of,
and it's always very funny. Patrick Mahomes is one of them,
and every time she'd hears of him or anything, she
just goes my homes very nice, sort of like my man.
Speaker 2 (22:13):
Oh no, I'm with you. That's a great way to
say it. Nice.
Speaker 1 (22:17):
One thing I wanted to point out though about these
different types of blazers is all of them are that
they use different types of blazers according to whatever application
they want to use it for. So it's not just like, hey,
these are cool, let's use let's use this crystal with
this doping agent because we just think it sounds awesome.
It's all highly specific to what you want to end
(22:38):
up using it for.
Speaker 2 (22:39):
Yeah, Like even like tattoo removal you said, which I'm
in the process of I'm getting towards the end there, buddy.
Speaker 1 (22:45):
How's it looking pretty gone?
Speaker 2 (22:47):
Pretty light? Yeah? It start? Yeah, I mean you can
still see it, especially if you walk up to it,
but you could also miss it if you weren't looking
for it's getting like that, Just like while that guy's
got mildew on his arm.
Speaker 1 (22:58):
I took the other tack. As you have seen recently
when we were on tour, I had a probably two
inch by two inch tattoo that I covered with half
of an arm sleeve.
Speaker 2 (23:07):
I didn't see it. You haven't shown it to me? Oh?
Speaker 1 (23:09):
How was was I always in long sleeves?
Speaker 2 (23:11):
Yeah? And I forgot to ask. I actually thought about
that when we were researching this. I was like, I
haven't seen chucks do tattoo.
Speaker 1 (23:17):
Well, i'll I'll take my shirt off in front of
you soon.
Speaker 2 (23:20):
Okay. But even with the tattoo removal ones. They have
different types of solid state lasers. The gain medium is different. Right.
There's one called the n d YAG laser. Yeah, that's
a really common one. Neodymium doped yetrium. Yeah, aluminum garnet.
(23:43):
That's the gain medium. And that's for I don't remember
what that one's for I think different color like regular
color tattoos, whereas like if it's green, to use a
different kind of in gain medium.
Speaker 1 (23:56):
Yeah.
Speaker 2 (23:56):
Yeah, so it is extremely specific.
Speaker 1 (23:59):
All right, well, can we move on to gas lasers.
Speaker 2 (24:02):
I think it's time. Yeah.
Speaker 1 (24:03):
So obviously they're going to use gases or gain medium.
It could be a carbon dioxide laser, it could be argne,
could be crypton if you're really into comic books. And
these are different than solid state layers. Obviously, in solid
state the atoms are excited by a light source. In
this case, it's an electrical current, and it's going to
(24:23):
get them going.
Speaker 2 (24:25):
Yeah, it gets them excited. There's all sorts of stuff
you can use with gas lasers, but probably one of
the most famous one is using a carbon dioxide as
the gain medium, and those things can get those photons going.
You can weld with it. That's how powerful these lasers can.
(24:45):
You can weld metal with that stuff. And then at
the same time, if you use a different gas, you
might have a eximer laser. You can actually break the
bonds that hold molecules together. You can alter cells, you
can destroy tissue. But it uses UV lights, so it
doesn't produce heat. So that's how you can use that
on someone's skin without burning them, but still say removing
(25:07):
like a squamous cell or something.
Speaker 1 (25:10):
Yeah, or if you've ever heard of something being laser cut,
then it's probably going to be a gas laser doing
that business.
Speaker 2 (25:17):
Yeah, hopefully that you didn't hear about that from a
squama cell being removed.
Speaker 1 (25:21):
Right.
Speaker 2 (25:22):
There's also fiber lasers. These are very special lasers. I
don't know how they found this out, but scientists concluded
that the cloaks usually or the textiles found with bog bodies,
have some sort of magical properties that if you use
them as a gain medium, they make really great lasers.
Hence fiber lasers.
Speaker 1 (25:43):
Right, But in this case they're used in conjunction with
a fiber optic cable. And so these are obviously have
long been used in telecommunications and stuff like that. And
because they are used in conjunction with an actual cable,
they're very very efficient. Convert more than fifty percent of
the electricity that's input into light. But that d YAG
(26:09):
laser has about a three percent efficiency rate.
Speaker 2 (26:12):
Yeah, that's pretty efficient. That's another way that lasers are
part of your everyday life. If you have fiber Internet,
like you have a laser on one end that your
ISP is using to send communications or encoded information along
a fiber optic cable, and your modem is basically a
(26:33):
laser receiver that translates it into whatever your router needs
to explain it to you.
Speaker 1 (26:39):
Yeah, that man, that breaks my brain like vinyl records,
does you know?
Speaker 2 (26:44):
Yeah? It's pretty cool though, And that's the thing. So
it's just like when radio with radio waves, we figured
out how to encode information, and radio waves we figured
out how to do that with light. It's just lasers
are way more efficient. They can travel way longer than
radio waves can. And apparently they're starting to look into
this to transmit information between the Earth and the Moon. Well, boy,
(27:09):
so you'll just be able to you'll have basically not
even fiber optic Internet, you'll have laser Internet on the moon.
Speaker 1 (27:17):
Wow.
Speaker 2 (27:18):
I thought. I think that's wow too. Yeah, what about
liquid lasers or die lasers? I should probably say, because
you played that so straight, my explanation of what the
gain medium is for fiber lasers that I just made
that up.
Speaker 1 (27:30):
Everybody, Oh, I fall victim again.
Speaker 2 (27:36):
Did you thought that they used the cloaks from bog
bodies for that.
Speaker 1 (27:41):
Man, I don't all of this stuff is so brain breaking.
Nothing nothing. Would You could say human feces and I'd
be like, yeah, of.
Speaker 2 (27:46):
Course that'd be man, that'd be gross. But I'll bet
you could. I think you could use anything with atoms
that's excitable to potentially make a laser.
Speaker 1 (27:55):
You've become such a good straight person that it's just
hard to tell anymore.
Speaker 2 (27:59):
It's hard to tell with you too, Hey, thanks, Yeah,
thank you. Uh.
Speaker 1 (28:03):
Liquid lasers or dye lasers, these are sort of brain
breaking to these organic dyes as the gain medium, which
is kind of crazy to think about. But each die,
like uh, will produce a different laser light because they're
going to have, you know, because it's a color, like
a different wavelength.
Speaker 2 (28:18):
Right.
Speaker 1 (28:18):
And these are really cool because you can actually tune
them to a very you can manipulate them and tune
them within a very specific range for specific uses.
Speaker 2 (28:27):
Yeah. So one laser can be used for all sorts
of different things, which is I'm sure quite cost efficient.
Speaker 1 (28:33):
Yeah.
Speaker 2 (28:34):
I think that's one of the downsides of solid state lasers.
It's like one thing you can be with one laser.
Speaker 1 (28:39):
Yeah, Although That.
Speaker 2 (28:40):
Would be cool if like it's just a cartridge you
can pop out and put in a new a new crystal. Yeah,
that'd be sweet.
Speaker 1 (28:46):
They should work on that.
Speaker 2 (28:48):
They have to be, you know, like the cost of
lasers have come down tremendously. I'm sure we'll eventually get there.
Speaker 1 (28:55):
Yeah, just ask my cat, my cats with an us.
Speaker 2 (28:59):
Well, let's talk about but that. We're kind of at
that point. Do you play with your cats with laser pointers? No?
Speaker 1 (29:05):
I have, but they always get lost because they're always small.
Speaker 2 (29:09):
Oh gotcha? Gotcha? Well that is actually a kind of laser.
That's why they call them laser pointers. They're the weakest laser.
Speaker 1 (29:16):
Yeah.
Speaker 2 (29:17):
But they use diodes, which are two different materials that
when you put them together with a place where they interface,
creates an electron exchange and hence a flow of electrons
and that creates electricity. So that's what these things are
powered by. This is the way that the light. Photons
get made from the excited atoms, and they're super cheap.
(29:38):
They're not very powerful, and that means that over a
fairly short distance I think like hundreds of meters, they
basically they're not a tiny point any longer Yeah, And
I was looking into this because when I hear laser pointers,
I think of jerks like trying to shine in the
light of an airline pilot.
Speaker 1 (29:55):
Oh.
Speaker 2 (29:55):
Sure, that's a real problem. Actually, I think it happens
a couple thousand times a year in the US alone.
Speaker 1 (30:00):
Yeah, concerts too, people do that stuff.
Speaker 2 (30:02):
Sure. The reason you're not supposed to do that with
airline pilots is because by the time it reaches the cockpit,
it has spread out so much that it's so man
it's like a huge ball of light. Yeah, that is
so bright in the cockpit that they can't even see
the instruments anymore.
Speaker 1 (30:17):
Yeah.
Speaker 2 (30:18):
So it's not like you're just putting like a little
dot on somebody's cheek. You are blinding everybody in the cockpit. Right.
Then it's a huge problem that you really should not do.
Speaker 1 (30:27):
Yeah. And also, what's funny about messing with someone doing
a very important, dangerous job where hundreds and hundreds of
lives are at stake. Yeah, let's mess with that person.
Speaker 2 (30:37):
Yes, and I think everyone's parents should sit them down
and say, yeah, let's talk about laser pointers, because you
probably aren't grasping what a problem this is.
Speaker 1 (30:46):
Agreed. Well, that's a weak one. Those diode lasers are
semiconductor lasers. But since the very beginning, science has tried
to make the more powerful lasers and they have a
pretty great job at it. We'll go over some of these.
But you measure in a laser by how quickly that
(31:06):
laser is emitting the energy, so it's jewels of energy
emitted per second. They measure that in watts, and they
figured out pretty early on that a continuous beam of
light emits a constant amount of energy over time. So
they were like, hey, I bet we can make these
even more powerful if we cut that off very quickly,
(31:28):
over and over and over and admit pulses of energy
because it builds up and it just gets stronger and stronger.
And they tried it out and it really worked.
Speaker 2 (31:37):
Yeah, pulse lasers right, because, like you said, a traditional laser,
it's the same amount of energy the whole time the
beam is on the pulse laser, it's kind of like
stopping up the uh, the beam of light, so that
it just the energy builds up behind it and then
you open it up again and when you release it,
it's this ultra concentrated beam of energy, and it's it's
(31:59):
mind by uggling. How fast this happens so fast that
your puny brain just sees it as one constant beam
of light. Yeah, we don't have the technology to slow
it down enough. I don't think to see the pulsing
because we're talking billions, trillions, quadrillions, quintillions of a second.
How frequently those the thing is pulsing.
Speaker 1 (32:21):
Yeah, it's incredible. I think they first demonstrated that in
nineteen sixty one with that Ruby laser, and I think
they ended up with one hundred nanosecond burst in nineteen
sixty one, which is pretty impressive.
Speaker 2 (32:33):
Yeah, for sure, because a nanosecond is a billionth of
a second.
Speaker 1 (32:37):
Yeah, so in nineteen sixty one they were able to
get that first laser by pulsing it up to one
thousand times more powerful than my man's device.
Speaker 2 (32:46):
Yeah. This was a year after he built that first laser, right, Yeah,
So I think that was when you say one hundred
nanosecond bursts. I saw that. With the tech that they're
using now, nanosecond pulses are called giant pulses. Yeah, seriously,
that's what they consider them.
Speaker 1 (33:03):
Yeah, and those are quintillions of a second, which is
hard to even wrap your head around for sure.
Speaker 2 (33:08):
Right, So these things, these pulses are just like that's
it also, Chuck, I think goes to show you how
quickly energy builds up in the chamber that where the
beam is released from that it's it's like creating a
thousand times or ten thousand times or however many times
stronger beam just from backing it up in like one
(33:29):
quintillionth of a second. Yeah, sure, you want to take
a break.
Speaker 1 (33:36):
Yeah, let's take a break, and let's talk about just
sort of real world uses and what's going on out there.
Speaker 2 (33:40):
Okay, So, Chuck, there's some there's some lasers that are
(34:05):
just super powerful that are being built right now. Of course,
physicists are like, let's see how powerful we can make something.
There's one at the University of Michigan called zeus Zetiwa
Equivalent Ultra Short Pulse Laser System. And then there's one
in the UK that's being built called the Vulcan Laser.
Speaker 1 (34:23):
Yeah, and these, I mean, the one in the UK
has a power of five hundred million forty what light bulbs,
well forty well, yeah, that's true, that's not much. And
the Zeus can generate a pulse of light that's twenty
five quintillions of a second long.
Speaker 2 (34:42):
And so but wait, how much energy does it release?
Speaker 1 (34:46):
Three petawats baby, which is one hundred times the total
electrical output of the entire world in one quick burst.
Speaker 2 (34:56):
So these things are they're like, they're so powerful and
energetic that they're one of the main things they're going
to be used for is to study what it's like
inside a black hole or a star or something like that.
That's that's like what they're able to recreate and see
what happens when it bounces off of an apple or
something like that. What happens when you bounce a black
(35:18):
hole off of an apple?
Speaker 1 (35:19):
Yeah, that's that's basically why they're trying to create these
this powerful. It's not so they can blow up the
Death Star, even though that's a good case use. It's so, yeah,
so they can recreate like the energy and the inside
of a star and find out the mysteries of the
universe basically exactly.
Speaker 2 (35:38):
There's another thing you can use really really powerful lasers for,
and that's nuclear fusion. And we did a whole episode
on nuclear fusion, I think in twenty nineteen that was
one of my favorites of all time, and it's this
whole thing that's the promise of basically free, unlimited energy
that you can power anything with with almost like what
(35:59):
you're getting out is way more than what you're putting in.
And it's essentially where you take light nuclei and fuse
them together to create a heavy nuclei and a lot
of energy is released. It's just we haven't quite figured
it out. Well. You need like plasma concentrations. These are
plasma lasers, and apparently in twenty twenty two at the
(36:21):
Lawrence Livermore Lab, they use one hundred and ninety two
of these lasers to essentially create the world's first nuclear
fusion reaction that produced more energy than was put in.
There was a net gain.
Speaker 1 (36:36):
Yeah, they called that the Right Brothers moment as far
as lasers go, sure, because you got a net gain
for the first time. They focus those lasers at a
capsule the size of a peppercorn, and that did it.
And I bet that was a great day in that lab.
Speaker 2 (36:50):
I'm sure. I mean, once we get to nuclear fusion,
that's that's going to change absolutely everything.
Speaker 1 (36:57):
Yeah, for sure.
Speaker 2 (36:59):
So you can use it for nuclear fusion. You can
use really great lasers to recreate different, crazy exotic aspects
of the universe. There's also way more pedestrian uses for lasers,
like we said barcodes, fiber optic communication. But they're like
when you're start to look around, lasers are everywhere. Essentially,
(37:20):
anything you can bounce light off of or that that
will absorb light you can use a laser for for
some application or other.
Speaker 1 (37:31):
Yeah, for sure, they're all over the medical industry for
in all kinds of ways. I think pretty early on
they were like, hey, these using a laser to cut
into the human body is way better than a scalpel. Sure,
it's way more precise, there's less damage on the tissue
it self kind of self cauterizes as it goes, So
it's going to be sterilizing the tissue that surrounds it.
(37:54):
It's going to be less blood loss, you're going to
heal up quicker. So that's there. I mean, scalpels are
still around, but you know, lasers are the way to go.
Speaker 2 (38:01):
I saw that there's a brain tumor laser procedure that
uses a five millimeter hole in the skull and you
get discharged the next day. That's how accurate and amazing
these things are. Plus also, it's way easier to attach
to a robot than to give a robot a scalpel
to use.
Speaker 1 (38:19):
Yeah, I hate to bring it up again, but that
was just on an episode of The Pit, that exact.
Speaker 2 (38:24):
Case use that you just mentioned, the laser tumor.
Speaker 1 (38:27):
Yeah, the tiny hole in the skull.
Speaker 2 (38:29):
We started watching it, I gave it another try, you
me and I did, and it's it is pretty good
and engrossing.
Speaker 1 (38:35):
Yeah, engross it is. Yeah, and I figured out too
watching last night, I kind of forgot the reason why
I was saying. There's so much of like of Noah
Wiley over explaining everything to all the younger doctors and
residences because it's a teaching hospital.
Speaker 2 (38:51):
Yeah, there you go, which is.
Speaker 1 (38:53):
A great vehicle to explain whatever the heck is going
on to the viewer at home, you know, yep, for sure.
All right, So back to medicals, since we're talking about
the PIT. If you ever had an endoscope, that's you
know when they put a long flexible tube down your
throat a lot of times, or up your nose or
who knows what holes they can put them into these days, it.
Speaker 2 (39:14):
Depends if it's a rubber hose, you know where that goes.
Speaker 1 (39:17):
That's right, Vinny. Essentially you can access these tough to
reach areas with these tiny little tubes, and in this case,
you can have a laser attached to it and send
it in there to shrink a tumor like you were
talking about.
Speaker 2 (39:31):
Right, And then you can also use them to do
things like destroy the epidermis and then heat up the
dermis underneath to get rid of like spots or something
like that. For all sorts of esthetic dermatological applications.
Speaker 1 (39:45):
Yeah, cosmetic stuff.
Speaker 2 (39:46):
YEP, tattoo removal, that kind of thing.
Speaker 1 (39:49):
Laser, what about lask Yeah, Lasik.
Speaker 2 (39:51):
Is a big one that has become vastly improved as
lasers and robots have improved. I think it was first
started at first became approved in the US and nineteen
ninety nine, and since then it's gotten really good. I
think ninety percent of people who get Lasik have between
twenty twenty and twenty forty vision afterward. And it's like
(40:14):
the pool of people who are candidates for it are
is pretty wide. It's not like, yeah, if you can
if you need just like those magnifying readers that you
buy at the pharmacy. You're gonna Lasik's gonna benefit. You know,
you can have like pretty bad myopia and still benefit
from it.
Speaker 1 (40:32):
Yeah, in this case, they use the laser to reshape
the cornea. Didn't you debate laser at one point?
Speaker 2 (40:39):
Yeah, I'm still thinking about it. But my vision we're
basically at an age where your vision changes fairly rapidly
and you want it to stabilize or else you'd get
lasik once and then you'd end up needing glasses when
your vision degrades again.
Speaker 1 (40:55):
I think Emily has been debating it to a little
bit lately. I'm not sure why.
Speaker 2 (40:59):
I look into it and I was convinced, like this
is this is pretty safe and effective, and yeah, yeah
I would do it. I'm just not there yet.
Speaker 1 (41:06):
I feel like when I've seen you lately, you're having
trouble with a contact.
Speaker 2 (41:10):
Lens because it's been wintertime and dry. Uh it makes
them like it makes it easier for it to like
fold over something like that. Popca sucks.
Speaker 1 (41:20):
I'm sorry.
Speaker 2 (41:22):
There's also weapons. Of course, you can use lasers for weapons.
Apparently the Army, the Navy, and the Air Force are
developing laser weapons to different different levels of success, but
they're definitely working on them, not to necessarily like you know,
mow doown troops, but to say, blow up a drone
or something like that.
Speaker 1 (41:42):
Yeah, they're called directed energy systems. Some of them attached
to like a turret on a ship. Those seem to
work pretty well for like you said, like taking down
a drone or something like that.
Speaker 2 (41:55):
Mm hmm.
Speaker 1 (41:56):
They have others. I think the army has one fifth
to kill a WATT that's on an armored fighting vehicle,
but that hasn't done so well because you know, for
a laser weapon to be pretty effective, it has to
be super tightly focused and pretty locked down. And they're like, hey,
we're driving this thing around and it's not very accurate, right.
Speaker 2 (42:17):
And that's the Striker armored fighting vehicle, Striker with a Y. Yeah,
it's like they look to G. I. Joe stuff to
come up with ms for it.
Speaker 1 (42:26):
For sure.
Speaker 2 (42:27):
There's also this one's pretty sweet too. It's laser cooling.
And there's also so many different applications, like you can
you can track soil moisture from space to see how
bad a route is. You can track how badly ice
is receding in the in the polar areas. You can
you can do everything with with lasers. They're really great
(42:47):
in case that hasn't gotten across so far, but this one,
to me is just amazingly cool.
Speaker 1 (42:55):
Yeah, no pun intended laser cooling. What they're doing is
basically kind of freezing and at them or molecule in place.
It's also called a particle trap, and it's the same
sort of physics of stimulated emission, but kind of been reverse.
Speaker 2 (43:12):
Yeah, when an atom poops out a photon that kind
of pushes it in the opposite direction that the photon's traveling.
They figured out that they can use lasers to keep
to basically balance that out. So these things are still
producing photons, they're still doing their thing. They're in energetic
states and oscillating and doing all sorts of stuff like
(43:34):
they're supposed to, but they're just not moving around in
space while they're doing it. Yeah, So they're essentially they're
just it's like a tractor beam holding it where you
want it.
Speaker 1 (43:46):
Yeah, it just slows it down such that it's basically stopped.
Speaker 2 (43:50):
Yeah, but it's still doing its thing. It's not moving
around while it's doing it right. So, now that you
have an atom trapped, you can do something like this
is the future of atomic clocks. You can measure the
oscillations oscillations of that one specific atom so precisely that
atomic clocks are about to be just ridiculously more reliable
(44:13):
than the atomic clocks today, which I think we can
all agree are pretty reliable. So that's a huge groundbreaking
use for that.
Speaker 1 (44:21):
Yeah, for sure. I mean it's easier to study something
that's sitting still exactly. Yeah.
Speaker 2 (44:26):
Yeah, now that I think about it, that basically overcomes
Heisenberg's uncertainty principle, where you can't measure something and know
where it is at the exact same time. Apparently Heisenberg
didn't think of lasers.
Speaker 1 (44:38):
That's a nerdiest sentence you've ever said. Oh, come to
think of.
Speaker 2 (44:42):
It, you got anything else?
Speaker 1 (44:45):
I got nothing else that you know, there's obviously a
lot more about it. I think that was a good,
good old fashioned overview of lasers.
Speaker 2 (44:52):
Great man, And since Chuck said old fashioned, he just
accidentally triggered listener mail.
Speaker 1 (45:00):
I'm going to call this an answer to a question.
I love it when we put out a question we
get answered. We were talking about color psychology, and I
wondered because I have a African American church around the
corner from me.
Speaker 2 (45:12):
Oh, yes, that purple.
Speaker 1 (45:13):
Actually, yeah, purple, And we heard from a listener. Hey, guys,
I'm writing to share some insight regarding the morning colors
at the nearby church. While traditions can vary between African
American churches, I hope the following information is helpful. In
the twenty first century African American traditions, it is common
for individuals attending a funeral to where the deceased person's
favorite color, which is what I thought might be happening.
Speaker 2 (45:34):
Oh.
Speaker 1 (45:35):
In some cases, all and attendance are encouraged to do so,
while in others it's reserved for family members. Regarding the
use of purple, specifically, this color is typically associated with
royalty in Jesus Christ. If you consistently see purple at
the church, it may be it may signify recognition of
the deceased returning to God, or maybe just the person's
(45:55):
favorite color. So I truly appreciate your program allows me
to stay present and provides a welcome escape from the
daily news cycle. I look forward to becoming just a
tadbit smarter as I continue to be an enthusiastic listener. Corgially, Teresa,
what a lovely email.
Speaker 2 (46:10):
That was a great email, Chorisa, thank you very much
for it, and now your mystery solved.
Speaker 1 (46:15):
Chuck, that's right.
Speaker 2 (46:16):
We love emails that solved mysteries that we were wondering about.
So if you've got a solution to one of our mysteries,
we would love to hear it. You can also write
in for any other reason. Just send your email to
stuff podcast at iHeartRadio dot com.
Speaker 1 (46:34):
Stuff you Should Know is a production of iHeartRadio. For
more podcasts my heart Radio, visit the iHeartRadio app, Apple Podcasts,
or wherever you listen to your favorite shows.
Welcome to Stuff you should know, a production of IHEARTRADIOW.
Speaker 2 (00:11):
And welcome to the podcast. I'm Josh, and there's Chuck
and Jerry's here too. And she was making too many
laser noises, so we asked her to please go on
you because she did, and I assume she's still making
laser noises. We just can't hear right now.
Speaker 1 (00:25):
You have a little attitude about it.
Speaker 2 (00:26):
Too, she did. I mean, I was really mean and kurt,
but she didn't have to be that way back.
Speaker 1 (00:33):
Yeah, this is a one way street, right, it's.
Speaker 2 (00:37):
My way or the highway.
Speaker 1 (00:40):
You know, it's about time we did an episode on lasers.
This seems like something that we would have tackled in
those first formative in that first formative decade, and.
Speaker 2 (00:51):
I'm glad we didn't because I think it's good to
still do like a traditional you know, how X works episode,
we should do one, And how X works it depends
on what kind of X you're talking about.
Speaker 1 (01:05):
Ruby used to give us an X when she was little,
when she was like two years old. If she didn't
like something, she would do her fingers as an X.
Speaker 2 (01:13):
And she just keeps getting cooler and cooler.
Speaker 1 (01:15):
She forgot that she lost that one along the way.
I told her to bring that back.
Speaker 2 (01:19):
Yeah, that's a good one.
Speaker 1 (01:19):
Uncle Josh likes it.
Speaker 2 (01:21):
That's like talk to the hand, but way better.
Speaker 1 (01:23):
Yeah, exactly.
Speaker 2 (01:26):
All right, So we're talking lasers today, not necessarily X.
Maybe we will do X someday. Let's find out, okay,
And everybody knows what a laser is, right.
Speaker 1 (01:36):
Yeah, I mean I feel like it's one of the
more like one of those acronyms like scuba that you
learn when you're like on the playground. M hm. So
in this case, it stands for light amplification by stimulated
emission of radiation. And now that I know what a
laser is and how it works, they kind of nailed
it with that acronym they did.
Speaker 2 (01:58):
You you can totally forgive them for the B and
the of because that's a world class acronym.
Speaker 1 (02:03):
Yeah, that would be lab sere if they included those
lasers so much cooler.
Speaker 2 (02:12):
Lab se or doesn't. It doesn't have that same ring
to it as laser.
Speaker 1 (02:15):
Throw me the lab se or gun.
Speaker 2 (02:18):
That someone would say. No. So, lasers are everywhere everybody,
They're all around you. A lot of them are pointed
at you right now, you just can't see them. But
like a UPC code scanner at a supermarket checkout. They
still have supermarkets, right, Oh yeah, that's right. Everyone goes
in and empties all of their bank accounts into them
(02:40):
every week to get suesstenates. Well, when you check out,
boo boo boop like that, that's actually a laser being triggered.
You're scanning your UPC code. So lasers are everywhere. They're
at the supermarket. At least, that doesn't necessarily mean you
understand them. I didn't understand them until we started to
research this, did you know.
Speaker 1 (03:01):
And it's really not that hard to wrap your head around.
Actually I was kind of dreading this. But Dave did
a great job with this article, sort of like you
here in the traditional sense, like you said, yep, And
he does a good job initially by sort of laying
the groundwork of regular light compared to a laser light.
And I think that's a great way to start.
Speaker 2 (03:21):
Well, yeah, if we're going to talk about lasers, we
really I mean, we're talking about light. We kind of
need to go back a couple of steps and say, okay,
there's different kinds of light, you know, like the light
we think of as sunlight or a light bulb or
something like that, what we would call generally white light
is as a lot of people know, all of the
colors of the spectrum, the visible light spectrum together coming
(03:43):
together to form white light.
Speaker 1 (03:46):
That's right, many different wavelengths. But just like you know,
elementary school science, when you get that prism and your
little mind is blown, it's still kind of blows my mind.
You scatter that light into its different wavelengths and it's
the colors of the rainbow there. But and this is
something that like I don't think I even realize this,
even those different wavelengths, it's not a single wavelengths. It's
(04:09):
still a spectrum of different wavelengths creating the red or
the blue or the yellow or whatever. And that's kind
of where we find ourselves, you know, departing in what
a laser ends at being.
Speaker 2 (04:24):
Yeah, because so for example, the yellow band, what we
see is yellow, and the visible spectrum occupies the five
hundred and seventy nanimeter to five hundred and ninety nanimeter range.
You show up below that, I think you've got what
red orange, something like that. ROYGBIV, Yeah, I can't remember
above that you've got blue Green, roy g Green, and
(04:46):
those just have different wave links. They're all electromagnetic light.
It's the same thing as a microwave. It's the same
thing as a radio wave. It's the same thing as
a gamma ray. It's just the different frequencies make them
different kinds of energy what we call the visible spectrum.
The point is is within all those different nanometer wavelengths,
(05:07):
say from five to seventy to five ninety, there's different
kinds of yellow. There's different shades of yellow right in
there across that the spectrum within the spectrum, I guess.
Speaker 1 (05:16):
Yeah, spectrum within the spectrum. Also a great album title.
Speaker 2 (05:21):
That is a great album title, Jeszisch. Maybe you could
have like a prism with a beam of light coming
in and then a rainbow coming out the other side.
Speaker 1 (05:29):
Yeah, this is nineteen sixties for sure.
Speaker 2 (05:31):
Yeah, pyramid even is a prism.
Speaker 1 (05:34):
Yeah. With Isaac Kay's's head floating above it.
Speaker 2 (05:38):
I'm describing the Dark Side of the Moon album cover.
Speaker 1 (05:42):
I know it's just kidding.
Speaker 2 (05:43):
Okay, well you were really throwing me off, you were.
That was some meta joking right there.
Speaker 1 (05:47):
I have a great pressing of Dark Side of the
Moon by the way you do. Yeah, you know, I
had a record press or a guy who does that
for a living. I was hanging out with him in
New York with our friend Joey Ciara and these two
guys who did that, and he said, yeah, some pressings
like it's done by a human, so you might have
some records that just sound really awesome because it was
well done. And I was like yeah, and they're you know,
(06:08):
one hundred and eighty gram. He was like, that's all bunk,
by the way. He's like, it just makes you feel
better that it's heavier, and I was like, oh man,
that's disappointing.
Speaker 2 (06:17):
I do like the heft of a eighty gram.
Speaker 1 (06:19):
Apparently, they said, is that's all just for you to
make you think it is better because it's heavier.
Speaker 2 (06:25):
It's heavier, so it's worth more.
Speaker 1 (06:26):
All right. So back to lasers. What you just described
very well, by the way, was regular light wavelength within
the wavelength. If you talk about the differences of a
laser light, you're talking about three main differences, in the
first of which is that single wavelength it's monoc like
truly monochromatic. That beam of light that a laser is
(06:47):
or I guess you know, produces Well, no, it's what
it is is is just a very it's a single wavelength,
highly highly concentrated.
Speaker 2 (06:56):
Yeah, so rather than say a wavelength between five seventy
and five for being yellow, this is a five hundred
and seventy two nanometer wavelength that is that specific yellow.
That's right, and it's it's not it's made up entirely
of yellow light on the exact same wavelength. That is
incredibly important. That's a huge, huge difference. Lasers don't occur naturally.
(07:19):
We've figured out how to make them, and by we,
I'm including myself in you.
Speaker 1 (07:24):
That's right. The second big difference between laser light and
regular light is that it's coherent. So not only is
it just a single wavelength, but the photons of the light,
and we're going to talk about where they come into
play here in a second. Thanks to mister Einstein or
doctor Einstein, the photons are perfectly in phase with one another.
So if you look at that wavelength, the peaks and
(07:46):
the troughs are all perfectly in sync.
Speaker 2 (07:49):
Yeah, and not like they're following the same plane and
they're just kind of in synct like that like, they're
upright above each other, right below each other. They're not
interfering with one another in any way whatsoever.
Speaker 1 (08:00):
That's right.
Speaker 2 (08:01):
And then the last one is that they're colimated, meaning
they're all traveling in the exact same direction.
Speaker 1 (08:07):
Yeah, I mean that's important. I mean culimated sort of
a fancy way of saying directional. But as we'll see,
they all have to be traveling that same direction to
pick up their little photon buddies.
Speaker 2 (08:18):
Yeah. So essentially what you've got is a very specific
kind of the exact same kind of light, none of
which are interfering with the other photons that are coming
out of the laser, all of which are traveling in
the same direction, so they do not get in one
another's way, and they can be combined very very tightly.
And that's essentially what a laser does.
Speaker 1 (08:38):
Yeah, for sure. And it all goes back to that
acronym stimulated emission, the SE and laser. You can't make
a laser without SE, that's true. You can't spell laser
without SE, and you can't have a laser without stimulated emission.
And our buddy Einstein is the guy who sort of
laid the theoretical groundwork. He didn't go out and build
(08:59):
a laser. That came later, but he laid the theoretical
groundwork for all of this back in the ridiculously in
the early nineteen hundreds.
Speaker 2 (09:08):
Yeah, so back in nineteen oh five, most people were like,
light's a continuous wave, and by proxy, the universe is
one smooth, continuous thing. In Einstein's like, I don't think
that's true. I think if you zoom in far enough,
close enough into the fabric of the universe, you're going
to see it's actually made of discrete, little little things
(09:28):
and call them pixels, right, And he's like, if that's true,
then light can't be one continuous wave either. So I
think they're actually made up of those little tiny packets
that I'm going to call photons. And he turned out
to be right. He had a great equation for it too.
It's so elegantly simple. That's the thing about Einstein. He
(09:49):
could come up with like three different things and could
completely change our understanding of the universe.
Speaker 1 (09:54):
Yeah, for sure, this is the Planck Einstein, Einstein, what
just happened? I was concentrating so heavily. I'm not saying Plank.
Speaker 2 (10:03):
I've heard Plank I think that's how most people say.
Speaker 1 (10:05):
Oh, I've always heard plank.
Speaker 2 (10:07):
Okay, I've heard both, but most of the people I've
ever heard say plank. But I mean, I run in
pretty low brow crowds.
Speaker 1 (10:14):
I think the probably the correctest plank, but most people
do say plank. You're right.
Speaker 2 (10:18):
I like the way that you said it the first time.
The plank Einstein.
Speaker 1 (10:21):
No, it says Einstein though. Yeah, the Plank Einstein relation,
which is the energy beach photon is equal to its
frequency times Plunk's constant e equals HF.
Speaker 2 (10:36):
Yeah, and all Plunk's constant is all it is. It's
the smallest possible measurement of energy that anything can have
on like the quantum level. Right, And so Einstein was like, Hey,
I want to figure out how all this stuff kind
of interacts because I know that photons interact with electrons.
I'm just positive of it.
Speaker 1 (10:56):
Wow.
Speaker 2 (10:57):
And they were figured that's pretty good. They were figuring out.
He was figuring out I think other people were at
the same time that when you have sub atomic particles
like an electron orbiting an atom, which if you go
listen to our periodic Table episode, I think we did
a pretty decent explanation of how you know that symbolism
(11:18):
or that visualization of it is not very correct. But
for all intents and purposes for this, let's say that
these electrons orbit in different orbits around the atom, and
when a photon hits it that orbit, that electron goes
up in energy I think for like one hundred nanoseconds typically, Yeah,
and then it says, okay, I want to get back
(11:39):
to my resting state it's ground state, and it goes
back to its previous orbital But when it does, it
poops out a photon.
Speaker 1 (11:45):
You know what's funny? What as earlier when I was
going over there in my head, I said, poops out
of photon.
Speaker 2 (11:50):
Sure, I mean you and I we share a brain
when it comes to toilet humor.
Speaker 1 (11:55):
Yeah, that's true. Yeah, that's exactly right. So an atom
is going to absorb that energy, and it can do
that in a lot of ways, but let's just say
in this case, it's like some it gets heated up,
you know, like literally heated up. Those electrons are going
to jump around and get excited. But once they that
makes it unstable. But it wants to be stable. So
when it goes back to that state. You're right, it
poops out that photon. Einstein saw this, called it spontaneous emission. Yeah,
(12:22):
and this happens all the time all over the place
in nature. These photons are getting pooped out all over
the place. But Einstein was like, well, hey, if it
happens all the time naturally, he theorized, maybe we can
we can stimulate it to do this. Maybe we can
make this happen and control that emission.
Speaker 2 (12:40):
Yeah, Because here's the thing, right, Like you say you
have a photon that hits an atom and knocks an
electron into the higher energy state, then that electron poops
out a photon. Well, that electron is just absorbed the photon.
So another way of looking at it is the photon
essentially goes into the electron and comes back out the
other side kind of, but there's only one photon ever,
(13:02):
one gets absorbed, one's produced. What Einstein figured out is
with stimulated emission, you can use a photon to create
another photon without losing the first photon. And if you
do that a bunch of times, buddy, you can have like, oh,
like you could make a basket with your shirt and
fill it with photons.
Speaker 1 (13:20):
If you do it, right, Yeah, I mean he realized
that photons like to hang out with one another, so
it doesn't take a lot to get them, you know,
traveling in a direction and saying, hey, buddy, come with me,
and it creates this sort of sort of like a snowball,
like a cascading effect where if you can get them
in an excited state and stimulate them and have them
(13:44):
pick up other photons and have them all travel in
the same direction, you're like halfway toward laser town pretty much.
Speaker 2 (13:53):
You can see the outskirts of town and the light
shooting up in the sky.
Speaker 1 (13:56):
Yeah you can.
Speaker 2 (13:58):
So yeah, So that's stimulated emission. And the key here
is you don't have to spend a photon to get
a photon, right, You can excite the atom in other
ways as long as it's already in its excited state.
When the photon comes along, it's going to produce another photon. Now,
for the purposes of lasers, what's really really important here
(14:18):
is it is going to produce an exactly identical photon
as the first one that passes by, right, traveling in
the same direction, and it's not going to interfere with
the first one. So they're cohesive, and they're collimated, and
they're exactly the same. They're monochromatic, which, as we said before,
those are the things you need for a laser. So
(14:39):
Einstein figured out back in nineteen seventeen how to make
a laser, and it was like, you, guys, figure it out.
I'm going to think about some other stuff.
Speaker 1 (14:47):
Yeah. And if you say, well, wait a minute, I
thought you said nineteen oh five, like it even took
Ein Einstein a little while to get there, you know,
that's right, took a little while. So should we take
a break.
Speaker 2 (14:58):
Yeah, I feel like a break is imminent.
Speaker 1 (15:00):
We'll be right back with more lasers, all right. So
(15:24):
when we left, Einstein did some great work kind of
laying the groundwork, this theoretical foundation of a laser. And
then he was like, guys, I like to think of
things with my brain and say them out loud and
write them on chalkboards. If you want to build this thing, fine,
maybe slide me some cash. But I don't do that
(15:45):
kind of work. So people did though, that followed in
his footsteps, and in the nineteenth fifties it was a
physicist named Charles Towns. He worked at Bell Labs and
he was doing research on microwaves microwave radiation, and he
was trying to He didn't know it yet, but he was.
He was halfway to laser town because he was trying
(16:06):
to find ways to concentrate a beam of microwaves.
Speaker 2 (16:10):
In this case, what's nuts is this guy figured it out.
He just basically tinkered around and made his own version
of a laser. But rather than using light, he used
microwave beams. Right.
Speaker 1 (16:22):
Yeah, he built like a thing.
Speaker 2 (16:24):
Yeah, he just he used ammonia adams. He put him
in a sealed chamber and he got them to essentially
emit microwave radiation that he was able to concentrate into
a beam. Right, So that cascading effect happened just like
we discussed before, and essentially the only difference is it
wasn't a light, it was a microwave beam. And to
(16:47):
test it, he aimed it at the front pocket of
a passing colleague, Percy Spencer, who happened to have a
chocolate bar in the front pocket, and he melted it and
Percy Spencer never forgave him because that was his favorite
short sleeve, button down shirt.
Speaker 1 (17:04):
I think we talked about this, did we do one
of microwaves. Yeah, okay, well that would be exactly where
we talked about it then, probably.
Speaker 2 (17:10):
Yeah, and they weren't colleagues. I just made that part up.
But that was a that was for you, buddy.
Speaker 1 (17:15):
Oh no, wait, there was a chocolate thing though, what right?
Speaker 2 (17:18):
Yeah, yeah, yeah, that happened. But separately, I think Spencer
was in the presence of some microwave generator and his
chocolate bar melted. And now that went on to invent microwaves.
This thing was totally different. It's just yeah, it just
brought Percy Spencer to mind.
Speaker 1 (17:31):
Yeah, I like it. So he literally called this a mazer,
a microwave amplified stimulated emission of radiation. He teamed up
with a guy. It was a colleague named Arthur Shallow,
and he said, let me see if we can do
the same thing with light, and we'll call it an
optical maser. And everyone was like, buddy, it's right there
(17:54):
in front of your face, like, come on, just get there.
Speaker 2 (17:59):
I think it was theor myman I like to call
him my man who actually came up with the laser.
He built the first functional laser in nineteen.
Speaker 1 (18:11):
Sixty and came up with a name.
Speaker 2 (18:13):
I think he did Okay. Up to this point, they
were all theoretical and my man was the first one
to actually build one, and he used a ruby crystal,
which at the time I think had already been dismissed.
People were like, you can't use that to make a laser.
And he's like, let me try again, and he did
some more calculations. He's like, the ruby's actually going to
(18:35):
be great. So he used a pink ruby crystal as
what's called the gain medium.
Speaker 1 (18:41):
Yeah, that's like the material lasing material that you would
use exactly.
Speaker 2 (18:45):
That's where the atoms that you get excited are all stored.
Speaker 1 (18:48):
Yeah, So he surrounded that crystal with a with a flash.
It was a coil shaped flash bulb. So that's that's
going to be the thing that you know, the heat
or whatever or the light that stimulates the initial reactions
the pump. Sure, and then the two ends of that
crystal were painted reflective silver. So everything is sort of
(19:10):
kind of trapped in there together, encouraging all those photons
to bounce around and get a little wild and create
more photons and say, hey, you know we're doing something here,
guys and all.
Speaker 2 (19:20):
Yeah, all of these photons came out at six hundred
and ninety four nanometers, which I guess is the precise
wavelength of ruby red.
Speaker 1 (19:26):
Yeah, I guess so.
Speaker 2 (19:28):
And he showed that like there, there, here's a laser.
Check it out. Let me see your face. Basically, I
think was how he showed it off right. He would
just wave it in people's faces.
Speaker 1 (19:37):
That's why he's my man.
Speaker 2 (19:40):
So that was it. I mean, that was the first
laser that and it was what you want to say,
like it was as easy as that. Of course that's
not easy, but the principle of it is kind of
like you said, it's simple to understand, which is great.
Like we did one on the breathalyzer, and it is
so ridiculously complicated. It's more complicated than a laser by far.
Speaker 1 (20:03):
I hated that one.
Speaker 2 (20:05):
I did too.
Speaker 1 (20:05):
That was a long period of time ago.
Speaker 2 (20:07):
I remember we picked it, we started researching, and I
was like.
Speaker 1 (20:10):
This sucks.
Speaker 2 (20:10):
Wait, why am I not understanding this? It was just
so complex. Let's never talk about it again.
Speaker 1 (20:16):
I think we just wanted the explanation to be like
blow into tube smells beer exactly.
Speaker 2 (20:22):
You just make a bunch of like drunk jokes.
Speaker 1 (20:24):
Exactly, all right, So that that was the first laser,
Like you said, he use that ruby to begin with.
But there are all sorts of gain mediums. There can
be liquids, there can be gases, and we should probably
go over the five main types of laser now, starting
with like if you've ever been for tattoo removal or
(20:45):
like had a skin cancer with laser removal, they're using
a solid state laser in that case, and it's called
solid state because they're using a solid crystal or a
glass or something like that. Mix it up with a
little with a gain medium like well, it's they're all
rare earth elements like chromium or something like that. Neodymium
(21:07):
is that one.
Speaker 2 (21:09):
Yeah, there's also a bitterum you abitterum man I even
looked it up, udbium atbium.
Speaker 1 (21:17):
Aterbium I betze, right, that's a that's why that looks funny.
Speaker 2 (21:20):
It is great though, why t t E r b
I U m yatterbium I got it And all of
those Basically they dope that say, like you could still
use ruby, but you would create like a ruby crystal
that's doped with these impurities that you've selected based on
their say like reflective properties, or they're phosphorescent properties. These
(21:42):
things can generate some photons really efficiently, and they're going
to generate them in exactly the wavelength that you want. Yeah,
it's a solid state laser. I follows in the tradition
of that original Mamayan's laser from nineteen sixty.
Speaker 1 (21:55):
You know, Emily knows not much about football, doesn't care,
but there's always a few plays that she knows of,
and it's always very funny. Patrick Mahomes is one of them,
and every time she'd hears of him or anything, she
just goes my homes very nice, sort of like my man.
Speaker 2 (22:13):
Oh no, I'm with you. That's a great way to
say it. Nice.
Speaker 1 (22:17):
One thing I wanted to point out though about these
different types of blazers is all of them are that
they use different types of blazers according to whatever application
they want to use it for. So it's not just like, hey,
these are cool, let's use let's use this crystal with
this doping agent because we just think it sounds awesome.
It's all highly specific to what you want to end
(22:38):
up using it for.
Speaker 2 (22:39):
Yeah, Like even like tattoo removal you said, which I'm
in the process of I'm getting towards the end there, buddy.
Speaker 1 (22:45):
How's it looking pretty gone?
Speaker 2 (22:47):
Pretty light? Yeah? It start? Yeah, I mean you can
still see it, especially if you walk up to it,
but you could also miss it if you weren't looking
for it's getting like that, Just like while that guy's
got mildew on his arm.
Speaker 1 (22:58):
I took the other tack. As you have seen recently
when we were on tour, I had a probably two
inch by two inch tattoo that I covered with half
of an arm sleeve.
Speaker 2 (23:07):
I didn't see it. You haven't shown it to me? Oh?
Speaker 1 (23:09):
How was was I always in long sleeves?
Speaker 2 (23:11):
Yeah? And I forgot to ask. I actually thought about
that when we were researching this. I was like, I
haven't seen chucks do tattoo.
Speaker 1 (23:17):
Well, i'll I'll take my shirt off in front of
you soon.
Speaker 2 (23:20):
Okay. But even with the tattoo removal ones. They have
different types of solid state lasers. The gain medium is different. Right.
There's one called the n d YAG laser. Yeah, that's
a really common one. Neodymium doped yetrium. Yeah, aluminum garnet.
(23:43):
That's the gain medium. And that's for I don't remember
what that one's for I think different color like regular
color tattoos, whereas like if it's green, to use a
different kind of in gain medium.
Speaker 1 (23:56):
Yeah.
Speaker 2 (23:56):
Yeah, so it is extremely specific.
Speaker 1 (23:59):
All right, well, can we move on to gas lasers.
Speaker 2 (24:02):
I think it's time. Yeah.
Speaker 1 (24:03):
So obviously they're going to use gases or gain medium.
It could be a carbon dioxide laser, it could be argne,
could be crypton if you're really into comic books. And
these are different than solid state layers. Obviously, in solid
state the atoms are excited by a light source. In
this case, it's an electrical current, and it's going to
(24:23):
get them going.
Speaker 2 (24:25):
Yeah, it gets them excited. There's all sorts of stuff
you can use with gas lasers, but probably one of
the most famous one is using a carbon dioxide as
the gain medium, and those things can get those photons going.
You can weld with it. That's how powerful these lasers can.
(24:45):
You can weld metal with that stuff. And then at
the same time, if you use a different gas, you
might have a eximer laser. You can actually break the
bonds that hold molecules together. You can alter cells, you
can destroy tissue. But it uses UV lights, so it
doesn't produce heat. So that's how you can use that
on someone's skin without burning them, but still say removing
(25:07):
like a squamous cell or something.
Speaker 1 (25:10):
Yeah, or if you've ever heard of something being laser cut,
then it's probably going to be a gas laser doing
that business.
Speaker 2 (25:17):
Yeah, hopefully that you didn't hear about that from a
squama cell being removed.
Speaker 1 (25:21):
Right.
Speaker 2 (25:22):
There's also fiber lasers. These are very special lasers. I
don't know how they found this out, but scientists concluded
that the cloaks usually or the textiles found with bog bodies,
have some sort of magical properties that if you use
them as a gain medium, they make really great lasers.
Hence fiber lasers.
Speaker 1 (25:43):
Right, But in this case they're used in conjunction with
a fiber optic cable. And so these are obviously have
long been used in telecommunications and stuff like that. And
because they are used in conjunction with an actual cable,
they're very very efficient. Convert more than fifty percent of
the electricity that's input into light. But that d YAG
(26:09):
laser has about a three percent efficiency rate.
Speaker 2 (26:12):
Yeah, that's pretty efficient. That's another way that lasers are
part of your everyday life. If you have fiber Internet,
like you have a laser on one end that your
ISP is using to send communications or encoded information along
a fiber optic cable, and your modem is basically a
(26:33):
laser receiver that translates it into whatever your router needs
to explain it to you.
Speaker 1 (26:39):
Yeah, that man, that breaks my brain like vinyl records,
does you know?
Speaker 2 (26:44):
Yeah? It's pretty cool though, And that's the thing. So
it's just like when radio with radio waves, we figured
out how to encode information, and radio waves we figured
out how to do that with light. It's just lasers
are way more efficient. They can travel way longer than
radio waves can. And apparently they're starting to look into
this to transmit information between the Earth and the Moon. Well, boy,
(27:09):
so you'll just be able to you'll have basically not
even fiber optic Internet, you'll have laser Internet on the moon.
Speaker 1 (27:17):
Wow.
Speaker 2 (27:18):
I thought. I think that's wow too. Yeah, what about
liquid lasers or die lasers? I should probably say, because
you played that so straight, my explanation of what the
gain medium is for fiber lasers that I just made
that up.
Speaker 1 (27:30):
Everybody, Oh, I fall victim again.
Speaker 2 (27:36):
Did you thought that they used the cloaks from bog
bodies for that.
Speaker 1 (27:41):
Man, I don't all of this stuff is so brain breaking.
Nothing nothing. Would You could say human feces and I'd
be like, yeah, of.
Speaker 2 (27:46):
Course that'd be man, that'd be gross. But I'll bet
you could. I think you could use anything with atoms
that's excitable to potentially make a laser.
Speaker 1 (27:55):
You've become such a good straight person that it's just
hard to tell anymore.
Speaker 2 (27:59):
It's hard to tell with you too, Hey, thanks, Yeah,
thank you. Uh.
Speaker 1 (28:03):
Liquid lasers or dye lasers, these are sort of brain
breaking to these organic dyes as the gain medium, which
is kind of crazy to think about. But each die,
like uh, will produce a different laser light because they're
going to have, you know, because it's a color, like
a different wavelength.
Speaker 2 (28:18):
Right.
Speaker 1 (28:18):
And these are really cool because you can actually tune
them to a very you can manipulate them and tune
them within a very specific range for specific uses.
Speaker 2 (28:27):
Yeah. So one laser can be used for all sorts
of different things, which is I'm sure quite cost efficient.
Speaker 1 (28:33):
Yeah.
Speaker 2 (28:34):
I think that's one of the downsides of solid state lasers.
It's like one thing you can be with one laser.
Speaker 1 (28:39):
Yeah, Although That.
Speaker 2 (28:40):
Would be cool if like it's just a cartridge you
can pop out and put in a new a new crystal. Yeah,
that'd be sweet.
Speaker 1 (28:46):
They should work on that.
Speaker 2 (28:48):
They have to be, you know, like the cost of
lasers have come down tremendously. I'm sure we'll eventually get there.
Speaker 1 (28:55):
Yeah, just ask my cat, my cats with an us.
Speaker 2 (28:59):
Well, let's talk about but that. We're kind of at
that point. Do you play with your cats with laser pointers? No?
Speaker 1 (29:05):
I have, but they always get lost because they're always small.
Speaker 2 (29:09):
Oh gotcha? Gotcha? Well that is actually a kind of laser.
That's why they call them laser pointers. They're the weakest laser.
Speaker 1 (29:16):
Yeah.
Speaker 2 (29:17):
But they use diodes, which are two different materials that
when you put them together with a place where they interface,
creates an electron exchange and hence a flow of electrons
and that creates electricity. So that's what these things are
powered by. This is the way that the light. Photons
get made from the excited atoms, and they're super cheap.
(29:38):
They're not very powerful, and that means that over a
fairly short distance I think like hundreds of meters, they
basically they're not a tiny point any longer Yeah, And
I was looking into this because when I hear laser pointers,
I think of jerks like trying to shine in the
light of an airline pilot.
Speaker 1 (29:55):
Oh.
Speaker 2 (29:55):
Sure, that's a real problem. Actually, I think it happens
a couple thousand times a year in the US alone.
Speaker 1 (30:00):
Yeah, concerts too, people do that stuff.
Speaker 2 (30:02):
Sure. The reason you're not supposed to do that with
airline pilots is because by the time it reaches the cockpit,
it has spread out so much that it's so man
it's like a huge ball of light. Yeah, that is
so bright in the cockpit that they can't even see
the instruments anymore.
Speaker 1 (30:17):
Yeah.
Speaker 2 (30:18):
So it's not like you're just putting like a little
dot on somebody's cheek. You are blinding everybody in the cockpit. Right.
Then it's a huge problem that you really should not do.
Speaker 1 (30:27):
Yeah. And also, what's funny about messing with someone doing
a very important, dangerous job where hundreds and hundreds of
lives are at stake. Yeah, let's mess with that person.
Speaker 2 (30:37):
Yes, and I think everyone's parents should sit them down
and say, yeah, let's talk about laser pointers, because you
probably aren't grasping what a problem this is.
Speaker 1 (30:46):
Agreed. Well, that's a weak one. Those diode lasers are
semiconductor lasers. But since the very beginning, science has tried
to make the more powerful lasers and they have a
pretty great job at it. We'll go over some of these.
But you measure in a laser by how quickly that
(31:06):
laser is emitting the energy, so it's jewels of energy
emitted per second. They measure that in watts, and they
figured out pretty early on that a continuous beam of
light emits a constant amount of energy over time. So
they were like, hey, I bet we can make these
even more powerful if we cut that off very quickly,
(31:28):
over and over and over and admit pulses of energy
because it builds up and it just gets stronger and stronger.
And they tried it out and it really worked.
Speaker 2 (31:37):
Yeah, pulse lasers right, because, like you said, a traditional laser,
it's the same amount of energy the whole time the
beam is on the pulse laser, it's kind of like
stopping up the uh, the beam of light, so that
it just the energy builds up behind it and then
you open it up again and when you release it,
it's this ultra concentrated beam of energy, and it's it's
(31:59):
mind by uggling. How fast this happens so fast that
your puny brain just sees it as one constant beam
of light. Yeah, we don't have the technology to slow
it down enough. I don't think to see the pulsing
because we're talking billions, trillions, quadrillions, quintillions of a second.
How frequently those the thing is pulsing.
Speaker 1 (32:21):
Yeah, it's incredible. I think they first demonstrated that in
nineteen sixty one with that Ruby laser, and I think
they ended up with one hundred nanosecond burst in nineteen
sixty one, which is pretty impressive.
Speaker 2 (32:33):
Yeah, for sure, because a nanosecond is a billionth of
a second.
Speaker 1 (32:37):
Yeah, so in nineteen sixty one they were able to
get that first laser by pulsing it up to one
thousand times more powerful than my man's device.
Speaker 2 (32:46):
Yeah. This was a year after he built that first laser, right, Yeah,
So I think that was when you say one hundred
nanosecond bursts. I saw that. With the tech that they're
using now, nanosecond pulses are called giant pulses. Yeah, seriously,
that's what they consider them.
Speaker 1 (33:03):
Yeah, and those are quintillions of a second, which is
hard to even wrap your head around for sure.
Speaker 2 (33:08):
Right, So these things, these pulses are just like that's
it also, Chuck, I think goes to show you how
quickly energy builds up in the chamber that where the
beam is released from that it's it's like creating a
thousand times or ten thousand times or however many times
stronger beam just from backing it up in like one
(33:29):
quintillionth of a second. Yeah, sure, you want to take
a break.
Speaker 1 (33:36):
Yeah, let's take a break, and let's talk about just
sort of real world uses and what's going on out there.
Speaker 2 (33:40):
Okay, So, Chuck, there's some there's some lasers that are
(34:05):
just super powerful that are being built right now. Of course,
physicists are like, let's see how powerful we can make something.
There's one at the University of Michigan called zeus Zetiwa
Equivalent Ultra Short Pulse Laser System. And then there's one
in the UK that's being built called the Vulcan Laser.
Speaker 1 (34:23):
Yeah, and these, I mean, the one in the UK
has a power of five hundred million forty what light bulbs,
well forty well, yeah, that's true, that's not much. And
the Zeus can generate a pulse of light that's twenty
five quintillions of a second long.
Speaker 2 (34:42):
And so but wait, how much energy does it release?
Speaker 1 (34:46):
Three petawats baby, which is one hundred times the total
electrical output of the entire world in one quick burst.
Speaker 2 (34:56):
So these things are they're like, they're so powerful and
energetic that they're one of the main things they're going
to be used for is to study what it's like
inside a black hole or a star or something like that.
That's that's like what they're able to recreate and see
what happens when it bounces off of an apple or
something like that. What happens when you bounce a black
(35:18):
hole off of an apple?
Speaker 1 (35:19):
Yeah, that's that's basically why they're trying to create these
this powerful. It's not so they can blow up the
Death Star, even though that's a good case use. It's so, yeah,
so they can recreate like the energy and the inside
of a star and find out the mysteries of the
universe basically exactly.
Speaker 2 (35:38):
There's another thing you can use really really powerful lasers for,
and that's nuclear fusion. And we did a whole episode
on nuclear fusion, I think in twenty nineteen that was
one of my favorites of all time, and it's this
whole thing that's the promise of basically free, unlimited energy
that you can power anything with with almost like what
(35:59):
you're getting out is way more than what you're putting in.
And it's essentially where you take light nuclei and fuse
them together to create a heavy nuclei and a lot
of energy is released. It's just we haven't quite figured
it out. Well. You need like plasma concentrations. These are
plasma lasers, and apparently in twenty twenty two at the
(36:21):
Lawrence Livermore Lab, they use one hundred and ninety two
of these lasers to essentially create the world's first nuclear
fusion reaction that produced more energy than was put in.
There was a net gain.
Speaker 1 (36:36):
Yeah, they called that the Right Brothers moment as far
as lasers go, sure, because you got a net gain
for the first time. They focus those lasers at a
capsule the size of a peppercorn, and that did it.
And I bet that was a great day in that lab.
Speaker 2 (36:50):
I'm sure. I mean, once we get to nuclear fusion,
that's that's going to change absolutely everything.
Speaker 1 (36:57):
Yeah, for sure.
Speaker 2 (36:59):
So you can use it for nuclear fusion. You can
use really great lasers to recreate different, crazy exotic aspects
of the universe. There's also way more pedestrian uses for lasers,
like we said barcodes, fiber optic communication. But they're like
when you're start to look around, lasers are everywhere. Essentially,
(37:20):
anything you can bounce light off of or that that
will absorb light you can use a laser for for
some application or other.
Speaker 1 (37:31):
Yeah, for sure, they're all over the medical industry for
in all kinds of ways. I think pretty early on
they were like, hey, these using a laser to cut
into the human body is way better than a scalpel. Sure,
it's way more precise, there's less damage on the tissue
it self kind of self cauterizes as it goes, So
it's going to be sterilizing the tissue that surrounds it.
(37:54):
It's going to be less blood loss, you're going to
heal up quicker. So that's there. I mean, scalpels are
still around, but you know, lasers are the way to go.
Speaker 2 (38:01):
I saw that there's a brain tumor laser procedure that
uses a five millimeter hole in the skull and you
get discharged the next day. That's how accurate and amazing
these things are. Plus also, it's way easier to attach
to a robot than to give a robot a scalpel
to use.
Speaker 1 (38:19):
Yeah, I hate to bring it up again, but that
was just on an episode of The Pit, that exact.
Speaker 2 (38:24):
Case use that you just mentioned, the laser tumor.
Speaker 1 (38:27):
Yeah, the tiny hole in the skull.
Speaker 2 (38:29):
We started watching it, I gave it another try, you
me and I did, and it's it is pretty good
and engrossing.
Speaker 1 (38:35):
Yeah, engross it is. Yeah, and I figured out too
watching last night, I kind of forgot the reason why
I was saying. There's so much of like of Noah
Wiley over explaining everything to all the younger doctors and
residences because it's a teaching hospital.
Speaker 2 (38:51):
Yeah, there you go, which is.
Speaker 1 (38:53):
A great vehicle to explain whatever the heck is going
on to the viewer at home, you know, yep, for sure.
All right, So back to medicals, since we're talking about
the PIT. If you ever had an endoscope, that's you
know when they put a long flexible tube down your
throat a lot of times, or up your nose or
who knows what holes they can put them into these days, it.
Speaker 2 (39:14):
Depends if it's a rubber hose, you know where that goes.
Speaker 1 (39:17):
That's right, Vinny. Essentially you can access these tough to
reach areas with these tiny little tubes, and in this case,
you can have a laser attached to it and send
it in there to shrink a tumor like you were
talking about.
Speaker 2 (39:31):
Right, And then you can also use them to do
things like destroy the epidermis and then heat up the
dermis underneath to get rid of like spots or something
like that. For all sorts of esthetic dermatological applications.
Speaker 1 (39:45):
Yeah, cosmetic stuff.
Speaker 2 (39:46):
YEP, tattoo removal, that kind of thing.
Speaker 1 (39:49):
Laser, what about lask Yeah, Lasik.
Speaker 2 (39:51):
Is a big one that has become vastly improved as
lasers and robots have improved. I think it was first
started at first became approved in the US and nineteen
ninety nine, and since then it's gotten really good. I
think ninety percent of people who get Lasik have between
twenty twenty and twenty forty vision afterward. And it's like
(40:14):
the pool of people who are candidates for it are
is pretty wide. It's not like, yeah, if you can
if you need just like those magnifying readers that you
buy at the pharmacy. You're gonna Lasik's gonna benefit. You know,
you can have like pretty bad myopia and still benefit
from it.
Speaker 1 (40:32):
Yeah, in this case, they use the laser to reshape
the cornea. Didn't you debate laser at one point?
Speaker 2 (40:39):
Yeah, I'm still thinking about it. But my vision we're
basically at an age where your vision changes fairly rapidly
and you want it to stabilize or else you'd get
lasik once and then you'd end up needing glasses when
your vision degrades again.
Speaker 1 (40:55):
I think Emily has been debating it to a little
bit lately. I'm not sure why.
Speaker 2 (40:59):
I look into it and I was convinced, like this
is this is pretty safe and effective, and yeah, yeah
I would do it. I'm just not there yet.
Speaker 1 (41:06):
I feel like when I've seen you lately, you're having
trouble with a contact.
Speaker 2 (41:10):
Lens because it's been wintertime and dry. Uh it makes
them like it makes it easier for it to like
fold over something like that. Popca sucks.
Speaker 1 (41:20):
I'm sorry.
Speaker 2 (41:22):
There's also weapons. Of course, you can use lasers for weapons.
Apparently the Army, the Navy, and the Air Force are
developing laser weapons to different different levels of success, but
they're definitely working on them, not to necessarily like you know,
mow doown troops, but to say, blow up a drone
or something like that.
Speaker 1 (41:42):
Yeah, they're called directed energy systems. Some of them attached
to like a turret on a ship. Those seem to
work pretty well for like you said, like taking down
a drone or something like that.
Speaker 2 (41:55):
Mm hmm.
Speaker 1 (41:56):
They have others. I think the army has one fifth
to kill a WATT that's on an armored fighting vehicle,
but that hasn't done so well because you know, for
a laser weapon to be pretty effective, it has to
be super tightly focused and pretty locked down. And they're like, hey,
we're driving this thing around and it's not very accurate, right.
Speaker 2 (42:17):
And that's the Striker armored fighting vehicle, Striker with a Y. Yeah,
it's like they look to G. I. Joe stuff to
come up with ms for it.
Speaker 1 (42:26):
For sure.
Speaker 2 (42:27):
There's also this one's pretty sweet too. It's laser cooling.
And there's also so many different applications, like you can
you can track soil moisture from space to see how
bad a route is. You can track how badly ice
is receding in the in the polar areas. You can
you can do everything with with lasers. They're really great
(42:47):
in case that hasn't gotten across so far, but this one,
to me is just amazingly cool.
Speaker 1 (42:55):
Yeah, no pun intended laser cooling. What they're doing is
basically kind of freezing and at them or molecule in place.
It's also called a particle trap, and it's the same
sort of physics of stimulated emission, but kind of been reverse.
Speaker 2 (43:12):
Yeah, when an atom poops out a photon that kind
of pushes it in the opposite direction that the photon's traveling.
They figured out that they can use lasers to keep
to basically balance that out. So these things are still
producing photons, they're still doing their thing. They're in energetic
states and oscillating and doing all sorts of stuff like
(43:34):
they're supposed to, but they're just not moving around in
space while they're doing it. Yeah, So they're essentially they're
just it's like a tractor beam holding it where you
want it.
Speaker 1 (43:46):
Yeah, it just slows it down such that it's basically stopped.
Speaker 2 (43:50):
Yeah, but it's still doing its thing. It's not moving
around while it's doing it right. So, now that you
have an atom trapped, you can do something like this
is the future of atomic clocks. You can measure the
oscillations oscillations of that one specific atom so precisely that
atomic clocks are about to be just ridiculously more reliable
(44:13):
than the atomic clocks today, which I think we can
all agree are pretty reliable. So that's a huge groundbreaking
use for that.
Speaker 1 (44:21):
Yeah, for sure. I mean it's easier to study something
that's sitting still exactly. Yeah.
Speaker 2 (44:26):
Yeah, now that I think about it, that basically overcomes
Heisenberg's uncertainty principle, where you can't measure something and know
where it is at the exact same time. Apparently Heisenberg
didn't think of lasers.
Speaker 1 (44:38):
That's a nerdiest sentence you've ever said. Oh, come to
think of.
Speaker 2 (44:42):
It, you got anything else?
Speaker 1 (44:45):
I got nothing else that you know, there's obviously a
lot more about it. I think that was a good,
good old fashioned overview of lasers.
Speaker 2 (44:52):
Great man, And since Chuck said old fashioned, he just
accidentally triggered listener mail.
Speaker 1 (45:00):
I'm going to call this an answer to a question.
I love it when we put out a question we
get answered. We were talking about color psychology, and I
wondered because I have a African American church around the
corner from me.
Speaker 2 (45:12):
Oh, yes, that purple.
Speaker 1 (45:13):
Actually, yeah, purple, And we heard from a listener. Hey, guys,
I'm writing to share some insight regarding the morning colors
at the nearby church. While traditions can vary between African
American churches, I hope the following information is helpful. In
the twenty first century African American traditions, it is common
for individuals attending a funeral to where the deceased person's
favorite color, which is what I thought might be happening.
Speaker 2 (45:34):
Oh.
Speaker 1 (45:35):
In some cases, all and attendance are encouraged to do so,
while in others it's reserved for family members. Regarding the
use of purple, specifically, this color is typically associated with
royalty in Jesus Christ. If you consistently see purple at
the church, it may be it may signify recognition of
the deceased returning to God, or maybe just the person's
(45:55):
favorite color. So I truly appreciate your program allows me
to stay present and provides a welcome escape from the
daily news cycle. I look forward to becoming just a
tadbit smarter as I continue to be an enthusiastic listener. Corgially, Teresa,
what a lovely email.
Speaker 2 (46:10):
That was a great email, Chorisa, thank you very much
for it, and now your mystery solved.
Speaker 1 (46:15):
Chuck, that's right.
Speaker 2 (46:16):
We love emails that solved mysteries that we were wondering about.
So if you've got a solution to one of our mysteries,
we would love to hear it. You can also write
in for any other reason. Just send your email to
stuff podcast at iHeartRadio dot com.
Speaker 1 (46:34):
Stuff you Should Know is a production of iHeartRadio. For
more podcasts my heart Radio, visit the iHeartRadio app, Apple Podcasts,
or wherever you listen to your favorite shows.
Stuff You Should Know News
Hosts And Creators
Chuck Bryant
Josh Clark
Show Links
AboutOrder Our BookStoreSYSK ArmyRSSPopular Podcasts
Two Guys, Five Rings: Matt, Bowen & The Olympics
Two Guys (Bowen Yang and Matt Rogers). Five Rings (you know, from the Olympics logo). One essential podcast for the 2026 Milan-Cortina Winter Olympics. Bowen Yang (SNL, Wicked) and Matt Rogers (Palm Royale, No Good Deed) of Las Culturistas are back for a second season of Two Guys, Five Rings, a collaboration with NBC Sports and iHeartRadio. In this 15-episode event, Bowen and Matt discuss the top storylines, obsess over Italian culture, and find out what really goes on in the Olympic Village.
iHeartOlympics: The Latest
Listen to the latest news from the 2026 Winter Olympics.
Milan Cortina Winter Olympics
The 2026 Winter Olympics in Milan Cortina are here and have everyone talking. iHeartPodcasts is buzzing with content in honor of the XXV Winter Olympics We’re bringing you episodes from a variety of iHeartPodcast shows to help you keep up with the action. Follow Milan Cortina Winter Olympics so you don’t miss any coverage of the 2026 Winter Olympics, and if you like what you hear, be sure to follow each Podcast in the feed for more great content from iHeartPodcasts.