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Scientists Create a Programmable Heat Switch · The Quark Side - Quantum Physics Podcast

• 0:01
  Speaker 1: Welcome to the quark Side Quantum Physics Podcast, an exploration
• 0:05
  Speaker 1: of the fundamental structure of reality where quantum laws govern matter, energy,
• 0:11
  Speaker 1: and information. Here, uncertainty is a feature, not a flaw,
• 0:16
  Speaker 1: and understanding begins with the smallest scales.
• 0:27
  Speaker 2: I want you to imagine a completely mind bending scenario
• 0:32
  Speaker 2: for a second.
• 0:33
  Speaker 3: I am listening.
• 0:34
  Speaker 2: So picture a physical material, like maybe a sleek, little
• 0:37
  Speaker 2: metallic panel, sitting on a desk right in front of
• 0:39
  Speaker 2: you right now. Imagine a concentrated beam of heat hits
• 0:44
  Speaker 2: this material from the right side. Naturally, the material absorbs
• 0:49
  Speaker 2: that thermal energy rip.
• 0:50
  Speaker 3: That is just basic physics.
• 0:51
  Speaker 2: Yeah, exactly. It starts getting warm. But here is the
• 0:55
  Speaker 2: bizarre part. Instead of eventually radiating some of that heat
• 0:59
  Speaker 2: back out towards the right side, it completely refuses to
• 1:03
  Speaker 2: emit heat in that direction. Really yeah, it acts like
• 1:07
  Speaker 2: an impenetrable brick wall to its own heat on that
• 1:09
  Speaker 2: right side. But then it turns around and radiates all
• 1:13
  Speaker 2: that absorbed heat straight out to the left side in
• 1:16
  Speaker 2: order to cool itself down. Wow, I know, right. It
• 1:19
  Speaker 2: takes heat in from one direction and exclusively shoots it
• 1:22
  Speaker 2: out in another.
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  Speaker 3: I mean, it sounds like a magic trick, or at
• 1:24
  Speaker 3: least a fundamental violation of how we intuitively understand the universe.
• 1:28
  Speaker 3: It really does, because when an object gets hot, we
• 1:32
  Speaker 3: expect it to glow, so to speak, in all the
• 1:34
  Speaker 3: ways it was capable of receiving that heat. A campfire
• 1:38
  Speaker 3: doesn't just radiate heat to the north.
• 1:40
  Speaker 2: No, it feels like a glitch in the matrix. But
• 1:42
  Speaker 2: this isn't science fiction. Okay, let's unpack this.
• 1:44
  Speaker 3: Let's do it.
• 1:45
  Speaker 2: We are looking at a groundbreaking new concept today, recently
• 1:48
  Speaker 2: published by researchers at Osaka Metropolitan University in the journal
• 1:52
  Speaker 2: Laser and Photonics Reviews.
• 1:54
  Speaker 3: A huge deal in that field.
• 1:55
  Speaker 2: Oh absolutely. It is a paradigm shift where heat can
• 2:00
  Speaker 2: actually be directed, steered, and literally programmed, almost exactly like
• 2:05
  Speaker 2: data routing through a microchip.
• 2:07
  Speaker 3: The implications here are just absolutely staggering from modern engineering.
• 2:11
  Speaker 3: I mean, we've spent the entire history of technology treating
• 2:14
  Speaker 3: heat as a stubborn, chaotic byproduct.
• 2:17
  Speaker 2: Yeah, just a massive annoyance exactly.
• 2:19
  Speaker 3: So the ability to direct it on purpose, but literally
• 2:22
  Speaker 3: tell heat exactly where it is allowed to go, well,
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  Speaker 3: that changes the foundational rules of how we build.
• 2:27
  Speaker 2: Machines, and that is exactly why we are bringing this
• 2:30
  Speaker 2: to you today. This isn't just a dry physics lesson.
• 2:33
  Speaker 3: Not at all.
• 2:33
  Speaker 2: This is a real tangible glimpse into the future of
• 2:36
  Speaker 2: how every single device around you, from the smartphone in
• 2:40
  Speaker 2: your pocket to the massive energy hungry server farms powering
• 2:44
  Speaker 2: the Internet, might very soon manage energy.
• 2:48
  Speaker 3: But to appreciate how revolutionary it is to steer heat
• 2:51
  Speaker 3: like this, we really need to take a step back, right.
• 2:54
  Speaker 3: We need to look at the invisible wall these researchers
• 2:57
  Speaker 3: had to break through before we could talk about how
• 3:00
  Speaker 3: Professor Koitici Yokomoto and doctor Shunsukeamurai managed to build this
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  Speaker 3: directional heat valve. We have to understand the fundamental physics
• 3:07
  Speaker 3: rule that made this seem well impossible for so long.
• 3:11
  Speaker 2: You're talking about the concept of reciprocity.
• 3:14
  Speaker 3: That's the one in the world of thermodynamics and optics.
• 3:16
  Speaker 3: Reciprocity is a very strict fundamental relationship.
• 3:19
  Speaker 2: Like an unbreakable rule.
• 3:21
  Speaker 3: Pretty much, it means that the way a material absorbs
• 3:24
  Speaker 3: heat and the way it emits heat are perfectly linked.
• 3:27
  Speaker 3: They are inseparable.
• 3:28
  Speaker 2: Okay, So how does that work in practice?
• 3:29
  Speaker 3: Well, let's say you have a specific surface, and it
• 3:32
  Speaker 3: is exceptionally good at absorbing thermal energy at a specific wavelength,
• 3:37
  Speaker 3: and it's best absorbing it when the heat arrives from
• 3:39
  Speaker 3: a specific angle.
• 3:40
  Speaker 2: Okay, So this hypothetical surface has a preferred flavor and
• 3:45
  Speaker 2: like a preferred angle for incoming heat.
• 3:48
  Speaker 3: Exactly, the law of reciprocity dictates that this exact same
• 3:52
  Speaker 3: surface is physically forced to emit heat in that exact
• 3:56
  Speaker 3: same way.
• 3:57
  Speaker 2: Oh, I get it.
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  Speaker 3: If it's a great absorber at that wavelength and direction,
• 4:02
  Speaker 3: it must be an equally great emitter at that wavelength
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  Speaker 3: and direction. The absorption and emission profiles are locked together
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  Speaker 3: in a perfect mirror image.
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  Speaker 2: Because nature demands this symmetry to maintain equilibrium.
• 4:15
  Speaker 3: Right, you hit the nail on the head.
• 4:16
  Speaker 2: It's kind of like a sponge. Think of a highly
• 4:19
  Speaker 2: porous sponge sitting on your kitchen counter.
• 4:21
  Speaker 3: Okay, picturing the sponge.
• 4:23
  Speaker 2: If it is incredibly porous on the top surface, it's
• 4:25
  Speaker 2: going to easily absorb water that is poured directly onto
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  Speaker 2: it from above, right, Right, But because of that exact
• 4:31
  Speaker 2: same physical structure, if you push down on that sponge,
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  Speaker 2: it's going to easily squeeze the water right back out
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  Speaker 2: through that same top surface exactly. Yes, the physical channels
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  Speaker 2: that let the water in are the literal pathways out.
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  Speaker 2: The structure is totally symmetrical.
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  Speaker 3: That physical pathway analogy is crucial here. The structural properties
• 4:49
  Speaker 3: governing the inflow and the outflow are one and the
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  Speaker 3: same at a microscopic level.
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  Speaker 2: But I'm going to play Devil's advocate for a second here.
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  Speaker 2: As an everyday person, symmetry sounds elegant. It's perfectly balanced.
• 5:01
  Speaker 2: So why is this natural symmetry actually a massive headache
• 5:06
  Speaker 2: for engineers who are trying to manage thermal energy in
• 5:09
  Speaker 2: modern technology?
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  Speaker 3: Well, this raises an important question because elegance in theoretical
• 5:14
  Speaker 3: physics is often an engineer's worst enemy. Ah, fair point,
• 5:18
  Speaker 3: reciprocity severely limits our ability to independently control heat. I mean,
• 5:23
  Speaker 3: think about modern electronics. We are packing billions of microscopic
• 5:27
  Speaker 3: transistors into chips the size of a fingernail.
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  Speaker 2: It's crazy when you really think about it.
• 5:32
  Speaker 3: It is, and they generate immense amounts heat, and that
• 5:35
  Speaker 3: heat is the ultimate killer of computing performance.
• 5:38
  Speaker 2: Oh yeah, we all know the sound of a laptop
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  Speaker 2: fan spinning up like a jet engine. When we open
• 5:41
  Speaker 2: too many browser tabs.
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  Speaker 3: Exactly. So, imagine you are an engineer trying to design
• 5:46
  Speaker 3: a passive system to pull that dangerous heat away from
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  Speaker 3: a highly sensitive processor. Because of reciprocity, heat is always
• 5:54
  Speaker 3: a two way street. If you design a material that
• 5:57
  Speaker 3: is highly efficient at pulling heat away from that processor,
• 6:01
  Speaker 3: that same material acts as a perfect bridge to radiate
• 6:04
  Speaker 3: heat right back into the processor. If the environmental conditions
• 6:08
  Speaker 3: shift even slightly.
• 6:09
  Speaker 2: Oh wow, I see, you can just build an exit
• 6:11
  Speaker 2: door because if it functions as a door, the heat
• 6:13
  Speaker 2: can use it to walk right back inside the building.
• 6:16
  Speaker 3: Exactly. You cannot design a device that safely and permanently
• 6:19
  Speaker 3: pulls heat away without the constant risk of it acting
• 6:23
  Speaker 3: as a two way conduit.
• 6:24
  Speaker 2: That is super frustrating.
• 6:25
  Speaker 3: You are constantly fighting against the materials innate desire to
• 6:28
  Speaker 3: reach equilibrium in both directions. This is why advanced thermal
• 6:32
  Speaker 3: management today is incredibly inefficient and bulky.
• 6:35
  Speaker 2: Right the giant fans yep.
• 6:36
  Speaker 3: We rely on elaborate active cooling systems, loud fans, massive
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  Speaker 3: copper heat sinks, and liquid cooling loops just to forcibly
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  Speaker 3: blow the heat away before it can travel back down
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  Speaker 3: the bridge.
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  Speaker 2: Okay, so, knowing that reciprocity is this unavoidable universal two
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  Speaker 2: way street really makes what the team out of Soccer
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  Speaker 2: Metropolitan University accomplished seem totally absurd.
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  Speaker 3: It really does.
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  Speaker 2: They somehow engineered a loop. They figured out a way
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  Speaker 2: to break the sponge. They completely separated the absorption of
• 7:05
  Speaker 2: heat from the emission of heat, and.
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  Speaker 3: They did it by looking beyond standard natural materials. They
• 7:10
  Speaker 3: had to create an entirely new composite structure to break
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  Speaker 3: that fundamental symmetry.
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  Speaker 2: Here's where it gets really interesting. They engineered a Frankenstein material.
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  Speaker 3: They did.
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  Speaker 2: They combined two completely different, highly specialized types of materials
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  Speaker 2: into a single device to force this one way street
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  Speaker 2: into existence. And the formal scientific term for what they
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  Speaker 2: build is a phase change magneto optical metigrading.
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  Speaker 3: It's quite a mouthful, I know, but breaking it down
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  Speaker 3: into its core components reveals a really brilliant mechanical logic.
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  Speaker 2: I'm going to stop you right there, though, because the
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  Speaker 2: first part of that, the magneto optical material, immediately breaks
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  Speaker 2: my brain.
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  Speaker 3: Oh really, how so.
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  Speaker 2: You're saying we are steering heat with magnets? I mean,
• 7:54
  Speaker 2: I thought magnets only affected metals like iron. Heat is
• 7:57
  Speaker 2: just thermal energy. How on Earth does a magnetic few
• 8:00
  Speaker 2: old sphear temperature.
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  Speaker 3: That is the perfect question, and it requires a quick
• 8:04
  Speaker 3: shift in how we think about heat. When we talk
• 8:07
  Speaker 3: about thermal radiation in this context, we aren't talking about
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  Speaker 3: hot air blowing around, Okay, we are talking about infrared light.
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  Speaker 3: Thermal energy is fundamentally electromagnetic radiation. It's just light that
• 8:21
  Speaker 3: our eyes can't see.
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  Speaker 2: Oh okay, so heat is light. That makes it way
• 8:24
  Speaker 2: easier to visualize.
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  Speaker 3: Right, And once you accept that heat is an electromagnetic wave,
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  Speaker 3: the magneto optical material actually makes.
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  Speaker 2: Sense because it interacts with light exactly.
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  Speaker 3: The defining property of these materials is that their interaction
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  Speaker 3: with light can be physically altered by applying a magnetic field.
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  Speaker 2: How does the magnet actually alter the light though?
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  Speaker 3: Well, the magnetic field breaks what physicists call time reversal
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  Speaker 3: symmetry for the light waves traveling through the material.
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  Speaker 2: Time reversal symmetry. Wait, are we talking about time travel now?
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  Speaker 1: Huh?
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  Speaker 3: Not quite? Yeah. Think of it like a video of
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  Speaker 3: a billiard ball bouncing off the cushion of a perfectly
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  Speaker 3: level pool. Table.
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  Speaker 2: Okay, got the visual.
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  Speaker 3: If you play that video in reverse, the ball's trajectory
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  Speaker 3: looks perfectly natural. You wouldn't even know the video is
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  Speaker 3: playing backwards. That is time reversal symmetry. The path works
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  Speaker 3: identically in both directions.
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  Speaker 2: Nice total sense.
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  Speaker 3: Now, imagine a slanted pool table. If you play a
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  Speaker 3: video in reverse of the ball rolling down that slant,
• 9:21
  Speaker 3: you'd suddenly see a ball defying gravity rolling uphill. It
• 9:25
  Speaker 3: immediately looks.
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  Speaker 2: Wrong, right, because gravity doesn't work that way exactly.
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  Speaker 3: The magnetic field applied to this material creates a sort
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  Speaker 3: of one way slope for the electromagnetic waves. It literally
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  Speaker 3: tilts the playing field. Wow, the light can travel smoothly
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  Speaker 3: in one direction, but the physics of the material actively
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  Speaker 3: resist the light traveling back the way it came.
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  Speaker 2: That is a phenomenal analogy. The magnet basically tilts the
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  Speaker 2: pool table for the infrared light. But a magnet is
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  Speaker 2: just a force. It doesn't give us a physical switch
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  Speaker 2: we can turn on and off inside the material itself
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  Speaker 2: to lock that pathway into place.
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  Speaker 3: Which brings us to the second component.
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  Speaker 2: They integrated, the phase change material called GST Exactly.
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  Speaker 3: GST stands for germanium and ammoni tlorium. It's a highly
• 10:10
  Speaker 3: specialized alloy. And what makes GST so critical here is
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  Speaker 3: that it can transition between two very different solid states.
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  Speaker 2: Okay, what are there?
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  Speaker 3: There is an amorphous state where its atoms are arranged chaotically,
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  Speaker 3: and a crystalline state, where its atoms are arranged in
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  Speaker 3: a highly ordered geometric grid.
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  Speaker 2: You know, usually when I hear phase change, I think
• 10:31
  Speaker 2: of water boiling into steam or freezing into ice.
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  Speaker 3: It's the same underlying concept of a substance altering its
• 10:38
  Speaker 3: physical properties, but it's happening entirely at a solid state level,
• 10:41
  Speaker 3: so it never melts. Right, The material never melts into
• 10:44
  Speaker 3: a liquid. Its internal atomic structure just completely rearranges itself
• 10:48
  Speaker 3: and critically. Its optical properties, like how it absorbs and
• 10:51
  Speaker 3: reflects that infrared heat, changed drastically depending on which state
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  Speaker 3: it is in.
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  Speaker 2: Wait, it's actually the same fundamental technology that we used
• 10:58
  Speaker 2: for decades to store data and rewriteable CDs and DVDs,
• 11:02
  Speaker 2: isn't it?
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  Speaker 3: It is the exact same family of materials.
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  Speaker 2: Yes, Like a laser burns a tiny spot to change
• 11:07
  Speaker 2: its state, making it either reflective or non reflective. To
• 11:10
  Speaker 2: read ones and zeros precisely.
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  Speaker 3: But here they aren't just using it to reflect a laser.
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  Speaker 3: They are using it to physically rebuild the pathways the
• 11:19
  Speaker 3: heat is trying to travel through.
• 11:20
  Speaker 2: So if we go back to the idea of a
• 11:23
  Speaker 2: room with a door, it's not just acting as a
• 11:25
  Speaker 2: switch that opens or closes. It's literally rearranging the furniture
• 11:30
  Speaker 2: in the room so the heat can't even find the door.
• 11:32
  Speaker 2: In the amorphous state, the atoms are like a chaotic
• 11:35
  Speaker 2: crowd of people blocking the exit. Heat gets trapped.
• 11:39
  Speaker 3: I love that visual So.
• 11:40
  Speaker 2: Then you apply a pulse of energy and those atoms
• 11:43
  Speaker 2: instantly form a disciplined crystalline grid, opening up a perfect
• 11:47
  Speaker 2: clear hallway for the heat to escape.
• 11:49
  Speaker 3: That is a very accurate way to visualize it. By
• 11:52
  Speaker 3: combining these two elements, by patterning the GST material on
• 11:55
  Speaker 3: top of the magneto optical material, they created what's called
• 11:58
  Speaker 3: a metigrating impact.
• 12:00
  Speaker 2: Metigrating for a second, we always throw around words like
• 12:02
  Speaker 2: microscopic structures, but why does the physical shape actually matter.
• 12:06
  Speaker 3: Well, ametigrating is a surface engineered with microscopic physical ridges
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  Speaker 3: and patterns. Think of the grooves on a vinyl record.
• 12:14
  Speaker 3: But scaled down so incredibly small that the size of
• 12:17
  Speaker 3: the grooves is roughly the exact same size as a
• 12:21
  Speaker 3: single wavelength of infrared light.
• 12:23
  Speaker 2: Oh wow, that is tiny.
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  Speaker 3: Very tiny, And because the physical geometry is the same
• 12:28
  Speaker 3: size as the light waves, it physically forces the light
• 12:32
  Speaker 3: to bend, trap, or guide itself in highly specific directions
• 12:36
  Speaker 3: based on how it hits those ridges.
• 12:38
  Speaker 2: Okay, so we have the magneto optical material tilting the
• 12:41
  Speaker 2: pool table, the GST physically rearranging the furniture to open
• 12:45
  Speaker 2: or close pathways, and the metigrating ridges physically guiding the
• 12:48
  Speaker 2: infrared waves exactly together, they actually built the one way
• 12:52
  Speaker 2: traffic valve for thermal energy. The heat comes in from
• 12:55
  Speaker 2: the right, but the material completely denies the heat the
• 12:58
  Speaker 2: ability to travel back to the right. It actively steers
• 13:01
  Speaker 2: it out to the left.
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  Speaker 3: It fully breaks reciprocity. It decouples absorption from emission in
• 13:07
  Speaker 3: a controllable, programmable way.
• 13:09
  Speaker 2: Okay, my mind is thoroughly blown by the physics here,
• 13:12
  Speaker 2: but I really have to ask cool for it. If
• 13:14
  Speaker 2: we have a slanted pool table and rearranged furniture, why
• 13:17
  Speaker 2: isn't this already inside my overheating laptop? Well, that's the catch, right,
• 13:21
  Speaker 2: Because building a one way street for heat in a
• 13:24
  Speaker 2: highly controlled laboratory setting is one thing to make it
• 13:27
  Speaker 2: actually useful for consumer electronics or industrial systems. The Osaka
• 13:32
  Speaker 2: researchers had to overcome two massive crippling flaws that plagued
• 13:37
  Speaker 2: earlier experimental versions of this technology.
• 13:39
  Speaker 3: That's entirely true. Breaking reciprocity has been a theoretical goal
• 13:43
  Speaker 3: for a very long time, and early prototypes did exist. Yeah,
• 13:47
  Speaker 3: but as you pointed out, they were incredibly fragile in
• 13:50
  Speaker 3: how they operated. Yeah. The first massive hurdle the researchers
• 13:53
  Speaker 3: overcame is what we call the angle problem.
• 13:56
  Speaker 2: Earlier devices were extremely picky about how the thermal radiation
• 13:59
  Speaker 2: actually hit them, right.
• 14:00
  Speaker 3: Extremely picky. Previous experimental devices only exhibited this non reciprocal behavior,
• 14:06
  Speaker 3: this one way heat flow if the thermal radiation arrived
• 14:08
  Speaker 3: at very large, extreme grazing angles.
• 14:11
  Speaker 2: Like trying to skip a stone across a pond. It
• 14:13
  Speaker 2: only works if the rock comes in low and fast exactly.
• 14:16
  Speaker 3: If the thermal radiation hit the material straight on or
• 14:19
  Speaker 3: even close to perfectly perpendicular, the one way effect vanished entirely.
• 14:23
  Speaker 3: It just broke down Yep, the device would basically revert
• 14:26
  Speaker 3: back to normal symmetrical behavior. The heat would just bounce
• 14:30
  Speaker 3: right back out the way it came.
• 14:31
  Speaker 2: Which makes those early devices completely useless for real world cooling.
• 14:36
  Speaker 2: Heat doesn't politely arrive at a perfect eighty degree grazing angle,
• 14:40
  Speaker 2: not at all. A hot processor radiates heat isotropically. It
• 14:43
  Speaker 2: blasts outward in every direction, all at once. You need
• 14:46
  Speaker 2: a material that can catch it dead.
• 14:48
  Speaker 3: On, and that is a major triumph of this new
• 14:52
  Speaker 3: GST magneto optical device. It achieves what the researchers call
• 14:57
  Speaker 3: giant non reciprocity even at near normal incidents.
• 15:00
  Speaker 2: Okay, translating your normal incidents. That basically means the heat
• 15:03
  Speaker 2: hits it straight on.
• 15:04
  Speaker 3: Yes, normal incidents means the light hits the surface perfectly
• 15:08
  Speaker 3: perpendicularly at a ninety degree angle to the surface. Achieving
• 15:12
  Speaker 3: giant non reciprocity here means the one way effect is
• 15:15
  Speaker 3: incredibly strong, not just barely detectable.
• 15:17
  Speaker 2: So it actually works.
• 15:19
  Speaker 3: This new device works brilliantly even when the thermal radiation
• 15:22
  Speaker 3: hits it almost straight on. It doesn't need the grazing
• 15:24
  Speaker 3: rock skip angle anymore. It functions in the messy multidirectional
• 15:28
  Speaker 3: reality of actual heat emission.
• 15:30
  Speaker 2: That alone takes this from a lab curiosity to a
• 15:33
  Speaker 2: truly viable technology. But there was a second massive flaw
• 15:38
  Speaker 2: with the old devices, and it has to do with
• 15:40
  Speaker 2: memory and power consumption.
• 15:42
  Speaker 3: Ah, yes, the power issue.
• 15:43
  Speaker 2: From what I gather, the older experimental materials had a
• 15:46
  Speaker 2: highly variable on and off switch, but much worse, they
• 15:50
  Speaker 2: entirely forgot their state the exact second the electrical power
• 15:53
  Speaker 2: was cut.
• 15:54
  Speaker 3: They were volatile. They required a constant, uninterrupted supply of
• 15:57
  Speaker 3: electrical energy just to maintain their megat magnetic fields and
• 16:00
  Speaker 3: their asymmetrical properties.
• 16:02
  Speaker 2: That seems counterproductive.
• 16:03
  Speaker 3: It was the moment you turned off the power, the
• 16:06
  Speaker 3: control mechanism would collapse and the material would instantly lose
• 16:10
  Speaker 3: its one way heat flow capability.
• 16:12
  Speaker 2: So it completely defeated the purpose. You were using a
• 16:14
  Speaker 2: massive amount of electricity, which generates heat, just to power
• 16:18
  Speaker 2: a device meant to manage heat.
• 16:20
  Speaker 3: Exactly, an endless loop of inefficiency.
• 16:22
  Speaker 2: Does this new device from the Osaka team solve that?
• 16:25
  Speaker 3: So?
• 16:26
  Speaker 2: Wait? Is this new device like a smart thermostat that
• 16:29
  Speaker 2: physically remembers its molecular setting even after you pull the plug.
• 16:32
  Speaker 3: What's fascinating here is that it solves it beautifully, and
• 16:35
  Speaker 3: it all goes back to that GST phase change material
• 16:38
  Speaker 3: we discussed earlier. Oh right. Because GST physically changes its
• 16:42
  Speaker 3: crystalline structure, literally rearranging its atoms, that structural change remains
• 16:48
  Speaker 3: permanently locked in even after the energy source used to
• 16:51
  Speaker 3: trigger the change is completely removed.
• 16:53
  Speaker 2: So it holds on to its programmed heat state indefinitely.
• 16:56
  Speaker 2: Zero power required to keep the settings locked in.
• 17:00
  Speaker 3: The structure itself is the memory. It's entirely non volatile.
• 17:03
  Speaker 3: You apply a tiny brief optical or electrical pulse to
• 17:07
  Speaker 3: set it to say, direct heat to the left, and
• 17:10
  Speaker 3: it stays that way until you specifically apply another active
• 17:13
  Speaker 3: pulse to change it back.
• 17:14
  Speaker 2: That is incredible.
• 17:15
  Speaker 3: It provides reversible on and off switching for heat flow
• 17:18
  Speaker 3: without requiring any ongoing electrical power to maintain the state.
• 17:22
  Speaker 2: So let's stick stock for a second. We now have
• 17:24
  Speaker 2: a highly efficient composite material. It steers heat in one direction,
• 17:29
  Speaker 2: It works when heat hits it straight on, and it
• 17:31
  Speaker 2: physically remembers its program state without needing a constant drip
• 17:35
  Speaker 2: of electricity.
• 17:36
  Speaker 3: We've conquered the physics.
• 17:37
  Speaker 2: Yes, So now we have to ask the big question,
• 17:40
  Speaker 2: what is the ultimate endgame for this technology? Way does
• 17:43
  Speaker 2: this actually take us?
• 17:44
  Speaker 3: The landscape of applications is incredibly broad. On the most
• 17:48
  Speaker 3: immediate practical level, we are looking at a new generation
• 17:51
  Speaker 3: of highly efficient infrared emitters and advanced thermal energy devices,
• 17:56
  Speaker 3: like what kind of devices think about space exploration? Managing
• 18:00
  Speaker 3: thermal energy precisely can literally be a matter of life
• 18:04
  Speaker 3: or death for a satellite.
• 18:06
  Speaker 2: Oh sure, because if a satellite is facing the blazing
• 18:09
  Speaker 2: sun on one side and the freezing vacuum of deep
• 18:11
  Speaker 2: space on the other, being able to actively force the
• 18:14
  Speaker 2: heat to only travel toward the deep space side without
• 18:17
  Speaker 2: it reflecting back into the delicate instruments, I mean that
• 18:20
  Speaker 2: would completely change how satellites are designed.
• 18:23
  Speaker 3: Absolutely. The researchers also point heavily toward advanced optical sensors
• 18:27
  Speaker 3: because you can control exactly how and where the material absorbs.
• 18:31
  Speaker 3: In for red light, you could design sensors that are hyperdirectional.
• 18:34
  Speaker 2: So they only look straight ahead exactly.
• 18:36
  Speaker 3: They could perfectly ignore all background thermal noise coming from
• 18:40
  Speaker 3: behind them and only focus on a specific target directly
• 18:44
  Speaker 3: in front of them.
• 18:45
  Speaker 2: But there is one application mentioned in the research that
• 18:47
  Speaker 2: feels completely out of a science fiction novel, and that
• 18:50
  Speaker 2: is photonic memory.
• 18:51
  Speaker 3: Photonic memory is where this technology truly leaps into the future. Currently,
• 18:57
  Speaker 3: almost all of our computing memory relies on store bring
• 19:00
  Speaker 3: electrical charges. We trap microscopic electrons in tiny silicon cells
• 19:05
  Speaker 3: to represent our digital ones and zeros.
• 19:07
  Speaker 2: And as we just established, forcing billions of electrical charges
• 19:10
  Speaker 2: through microscopic wires generates a massive amount of friction and heat, right,
• 19:15
  Speaker 2: which brings us right back to our original problem.
• 19:18
  Speaker 3: Exactly. But what if you completely remove the electrons from
• 19:21
  Speaker 3: the equation? What if you stored information using light and heat?
• 19:25
  Speaker 2: Let me make sure I'm following this. You could use
• 19:27
  Speaker 2: this new GST magneto optical material to build actual memory chips. Yes, exactly, So,
• 19:33
  Speaker 2: a digital one could physically be the state where the
• 19:35
  Speaker 2: material is crystallized and directs heat to the right, and
• 19:39
  Speaker 2: a digital zero could be the amorphous state where it
• 19:41
  Speaker 2: directs heat to the left.
• 19:42
  Speaker 3: And because it holds that structural state indefinitely without power,
• 19:47
  Speaker 3: it functions as non volatile memory, much like your computer's
• 19:50
  Speaker 3: solid state hard drive. That is wild, but it operates
• 19:53
  Speaker 3: entirely on thermal and optical principles rather than purely electronic ones.
• 19:59
  Speaker 3: Fund Men only changes the architecture of how we could
• 20:02
  Speaker 3: store data, potentially doing it way faster and with vastly
• 20:06
  Speaker 3: less energy waste.
• 20:07
  Speaker 2: So what does this all mean? When you synthesize all
• 20:10
  Speaker 2: these applications together, you start to see the sweeping vision
• 20:13
  Speaker 2: these researchers are pointing toward. We are looking at a
• 20:16
  Speaker 2: world where we actively intentionally control heat radiation in the
• 20:21
  Speaker 2: exact same way that modern electronic circuits currently control the
• 20:24
  Speaker 2: flow of electricity. We route it, we switch it, we
• 20:27
  Speaker 2: literally store data with it.
• 20:29
  Speaker 3: If we connect this to the bigger picture, it's about
• 20:32
  Speaker 3: a total perspective shift. Humanity has spent our entire industrial
• 20:36
  Speaker 3: history treating heat as a passive, annoying, and often destructive
• 20:40
  Speaker 3: byproduct of our machines.
• 20:42
  Speaker 2: Yeah, it was an enemy to be vented, fanned away,
• 20:44
  Speaker 2: or insulated against. It was essentially the exhaust pipe of progress.
• 20:48
  Speaker 2: You couldn't do anything useful with it. You just had
• 20:50
  Speaker 2: to make sure it didn't melt your engine.
• 20:52
  Speaker 3: But this breakthrough flips that script completely. By figuring out
• 20:56
  Speaker 3: how to break the law of reciprocity at a microscopic level,
• 21:00
  Speaker 3: we are turning heat into a programmable asset.
• 21:03
  Speaker 2: It's no longer just a chaotic waste.
• 21:05
  Speaker 3: Product exactly, it becomes a precise functional tool within the
• 21:09
  Speaker 3: system itself.
• 21:10
  Speaker 2: To briefly recap the journey we've just been on, we
• 21:13
  Speaker 2: started in a rigid universe completely defined by the unbreakable
• 21:17
  Speaker 2: law of reciprocity, where heat absorption and emission were stubbornly
• 21:21
  Speaker 2: locked together like a.
• 21:22
  Speaker 3: Sponge, unbreakable until now Right, and.
• 21:25
  Speaker 2: Thanks to the brilliant engineering of Professor Okamoto and doctor Murray,
• 21:29
  Speaker 2: who figured out how to combine time bending magneto optical
• 21:32
  Speaker 2: materials with shape shifting phase change memory, we have officially
• 21:36
  Speaker 2: stepped into a newly unlocked era of programmable heat.
• 21:39
  Speaker 3: An era where we have a one way valve for
• 21:41
  Speaker 3: thermal energy that works straight on in the real world
• 21:44
  Speaker 3: and actually remembers its job without needing a battery.
• 21:47
  Speaker 2: It really is incredible to think about the next time
• 21:50
  Speaker 2: you were trying to work and your laptop gets blazing hot,
• 21:53
  Speaker 2: burning your knees. I want you to remember this conversation
• 21:56
  Speaker 2: for sure, because very soon that heat isn't just going
• 21:59
  Speaker 2: to be an annoy pots. It is going to be
• 22:01
  Speaker 2: a perfectly directed, intelligently programmable stream of energy.
• 22:06
  Speaker 3: And it leaves you with a really fascinating thought to ponder.
• 22:10
  Speaker 3: If we can now program heat to travel in specific directions,
• 22:13
  Speaker 3: and if we can actually use it to store digital
• 22:16
  Speaker 3: data without any electrical power, Well, how long until the
• 22:20
  Speaker 3: very concept of a device overheating becomes entirely obsolete?
• 22:24
  Speaker 2: That is a crazy thought.
• 22:25
  Speaker 3: Imagine a future where our technology doesn't just survive its
• 22:28
  Speaker 3: own excess heat, but actively consumes that heat to perform faster,
• 22:33
  Speaker 3: more efficient computing.