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Scientists Reveal the Hidden Quantum World Inside Individual Molecules · The Quark Side - Quantum Physics Podcast

• 0:01
  Speaker 1: Welcome to the QuarkSide Quantum Physics Podcast, an exploration of
• 0:05
  Speaker 1: 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 at the smallest scales.
• 0:27
  Speaker 2: Right now, if you zoom in close enough to, like,
• 0:30
  Speaker 2: A single molecule. It isn't just sitting still.
• 0:33
  Speaker 3: Oh, absolutely not. It is constantly moving.
• 0:35
  Speaker 2: Right. It's vibrating. Its electrons are spinning. And energy is
• 0:39
  Speaker 2: basically shifting across these microscopic boundaries in this totally chaotic,
• 0:44
  Speaker 2: unending dance.
• 0:45
  Speaker 3: It really is a dance. And the problem is that
• 0:47
  Speaker 3: for decades, physicists have been completely blind to the specific
• 0:52
  Speaker 3: steps of that dance.
• 0:53
  Speaker 2: Yeah, which is crazy to think about. Our mission today
• 0:56
  Speaker 2: is to figure out exactly what is happening inside a
• 0:58
  Speaker 2: single molecule when it gets excited.
• 1:01
  Speaker 3: Exactly.
• 1:01
  Speaker 2: Because you know the energy is there, right? And you
• 1:04
  Speaker 2: can measure that a change has occurred. But pinpointing exactly
• 1:07
  Speaker 2: what kind of physical or quantum shift took place inside
• 1:11
  Speaker 2: that individual molecule, that has been one of the most
• 1:15
  Speaker 2: frustrating bottlenecks in modern physics.
• 1:16
  Speaker 3: It is incredibly frustrating. And it really stems from the
• 1:19
  Speaker 3: limits of our theoretical models when applied to systems that
• 1:21
  Speaker 3: are this small and, you know, this dynamic.
• 1:25
  Speaker 2: Because the macroscopic stuff is easier, right?
• 1:27
  Speaker 3: Yeah. At the macroscopic scale, physics behaves predictably. But down
• 1:30
  Speaker 3: at the level of a single molecule, you are dealing
• 1:33
  Speaker 3: with a many-body problem.
• 1:34
  Speaker 2: Meaning lots of moving parts all at once. Right.
• 1:38
  Speaker 3: You have dozens of interacting electrons and vibrating atomic nuclei.
• 1:42
  Speaker 3: The mathematical equations governing them become highly nonlinear, completely chaotic.
• 1:48
  Speaker 2: Right.
• 1:48
  Speaker 3: So when scientists try to read the quantum state of
• 1:50
  Speaker 3: a molecule during an experiment, they don't get this clean,
• 1:53
  Speaker 3: simple answer. They get a, clustered forest of spectral peaks
• 1:57
  Speaker 3: on a graph that are just, they're incredibly difficult to interpret.
• 2:01
  Speaker 2: Okay, let's unpack this for you listening, because I know
• 2:03
  Speaker 2: quantum physics can sound completely overwhelming. But the problem isn't
• 2:07
  Speaker 2: that scientists lack the tools to get a signal, right?
• 2:10
  Speaker 3: No, the measurement readouts exist. They have the data.
• 2:14
  Speaker 2: Right, but they are faced with this confusing variety of
• 2:17
  Speaker 2: excitations in those signals. So imagine you are listening to
• 2:21
  Speaker 2: a massively complex and dense musical chord played by an
• 2:25
  Speaker 2: entire orchestra. Uh-huh.
• 2:27
  Speaker 3: That's a good way to look at it.
• 2:28
  Speaker 2: You're standing behind a thick concrete wall and you hear
• 2:31
  Speaker 2: this loud volume spike. You know a sound was made, obviously.
• 2:35
  Speaker 3: Yeah, the signal's there. Right.
• 2:37
  Speaker 2: But the frequencies of all the instruments overlap perfectly, so
• 2:41
  Speaker 2: you have absolutely no idea if that specific acoustic spike
• 2:44
  Speaker 2: came from a cello being dropped or a bassoon or
• 2:48
  Speaker 2: a timpani drum.
• 2:49
  Speaker 3: And in the quantum realm, physicists have that exact same problem.
• 2:53
  Speaker 3: They have the signal, the thump through the wall, but
• 2:56
  Speaker 3: they are totally blind to the specific molecular process that
• 2:59
  Speaker 3: actually caused it.
• 3:01
  Speaker 2: Wow.
• 3:01
  Speaker 3: Which means any attempt at actually utilizing that molecule is
• 3:04
  Speaker 3: basically stalled right out of the gate.
• 3:06
  Speaker 2: Because you can't use what you don't understand.
• 3:08
  Speaker 3: Exactly. In physics, if you cannot identify the fundamental mechanism,
• 3:13
  Speaker 3: if you don't know which specific quantum excitation process lies
• 3:16
  Speaker 3: behind which measurement signal, you cannot control the system.
• 3:20
  Speaker 2: Right. You have the effect, but the cause is completely obscured.
• 3:23
  Speaker 1: Yeah.
• 3:24
  Speaker 3: And if your goal is to build advanced technology, like, say,
• 3:27
  Speaker 3: using molecular states to store or process information.
• 3:30
  Speaker 2: Which is the dream of quantum computing.
• 3:32
  Speaker 3: Exactly. But a system you can't control is worse than useless.
• 3:36
  Speaker 3: It is just generating random noise.
• 3:38
  Speaker 2: So that is the massive roadblock we are tackling today.
• 3:41
  Speaker 2: We need to know exactly what the molecule is doing.
• 3:44
  Speaker 2: But our instruments have historically just given us that ambiguous
• 3:48
  Speaker 2: orchestral noise. Right. Which brings us to a rather incredible,
• 3:52
  Speaker 2: honestly highly engineered setup designed by Dr. Arnab Banerjee and
• 3:56
  Speaker 2: his team at Keele University.
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  Speaker 3: Working alongside colleagues in San Sebastian, Spain.
• 3:59
  Speaker 1: Yes. Right.
• 4:01
  Speaker 2: And they realized they couldn't just untangle this mess on
• 4:04
  Speaker 2: a standard lab bench. They had to build the ultimate,
• 4:07
  Speaker 2: highly controlled stage for their experiment.
• 4:10
  Speaker 3: Yeah. The subject they chose for this stage is an
• 4:12
  Speaker 3: individual molecule called cobaltosine.
• 4:15
  Speaker 2: Cobaltosine. Right.
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  Speaker 3: It's this Fascinating organometallic structure. It's essentially a cobalt atom
• 4:23
  Speaker 3: sandwiched between two carbon rings.
• 4:25
  Speaker 2: Okay, sounds like a tiny microscopic sandwich.
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  Speaker 3: Pretty much. But what really matters here is the environment
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  Speaker 3: they engineered to observe it in. They placed this single
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  Speaker 3: cobaltocene molecule on a lead surface.
• 4:39
  Speaker 2: Just a piece of lead.
• 4:40
  Speaker 3: Well, yes, but they didn't leave it at room temperature.
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  Speaker 3: They cooled this lead surface down to near absolute zero.
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  Speaker 2: Wow.
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  Speaker 3: Yeah, reaching a temperature so extremely low that the lead
• 4:52
  Speaker 3: actually transitioned into a supliconducting state.
• 4:55
  Speaker 2: Now, wait, let me stop you right there and push
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  Speaker 2: back on this a bit.
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  Speaker 3: Sure.
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  Speaker 2: Because if you are listening to this and thinking about
• 5:00
  Speaker 2: the future of technology, this setup sounds wildly impractical.
• 5:05
  Speaker 3: Oh, it is extremely complex.
• 5:06
  Speaker 1: Right.
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  Speaker 2: I mean, we are talking about utilizing liquid helium, massive
• 5:10
  Speaker 2: cooling infrastructure, an ultra high vacuum just to isolate a
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  Speaker 2: single molecule on a superconducting surface.
• 5:16
  Speaker 1: Yes.
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  Speaker 2: If we have to go through all of this extreme
• 5:19
  Speaker 2: logistical expense just to read a signal, how is this
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  Speaker 2: ever going to translate into a practical... functioning quantum computer
• 5:27
  Speaker 2: that sits in a room somewhere or a server farm.
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  Speaker 2: It sounds like a purely academic exercise.
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  Speaker 3: Well, that is the exact skepticism you should have when
• 5:34
  Speaker 3: looking at foundational physics, honestly. But you have to separate
• 5:37
  Speaker 3: the discovery phase from the engineering phase.
• 5:40
  Speaker 2: Okay, fair enough.
• 5:41
  Speaker 3: You cannot build a commercial supersonic jet without first spending
• 5:45
  Speaker 3: years testing basic aerofoils in a highly controlled wind tunnel, right?
• 5:48
  Speaker 2: Right. So the extreme cold is the wind tunnel.
• 5:50
  Speaker 3: Precisely. It isolates the variables. Right now, physicists are just
• 5:54
  Speaker 3: trying to establish the ground truth of molecular behavior.
• 5:57
  Speaker 2: Makes sense.
• 5:58
  Speaker 3: But the superconductivity is even more crucial than just providing
• 6:01
  Speaker 3: a cold, quiet room. At room temperature, the environment is
• 6:04
  Speaker 3: just flooded with thermal energy.
• 6:07
  Speaker 2: So things are just bouncing around.
• 6:08
  Speaker 3: Exactly. Atoms are jiggling, creating thermal noise that would completely
• 6:12
  Speaker 3: drown out the really delicate quantum behaviors of that cobaltosine molecule.
• 6:17
  Speaker 2: Oh, I see.
• 6:18
  Speaker 3: But by dropping the temperature until the lead becomes superconducting,
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  Speaker 3: a fundamental shift happens in the material itself. The electrons
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  Speaker 3: in the lead pair up into what are called Cooper pairs.
• 6:28
  Speaker 2: Cooper pairs, okay.
• 6:29
  Speaker 3: And this creates a macroscopic quantum state with a very
• 6:33
  Speaker 3: specific hard energy gap.
• 6:35
  Speaker 2: And that energy gap acts like a filter.
• 6:38
  Speaker 3: It acts like a hyper-precise energetic baseline. Because of that gap,
• 6:42
  Speaker 3: there are no ambient low-energy electron states bouncing around to
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  Speaker 3: basically muddle the signal.
• 6:47
  Speaker 2: Wow.
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  Speaker 3: Yeah. So when the researchers finally probe the molecule, they
• 6:51
  Speaker 3: know the energy of that probe with breathtaking precision because
• 6:55
  Speaker 3: the superconducting surface has eliminated all the background static.
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  Speaker 2: Which sets the perfect stage for the tool they actually
• 7:01
  Speaker 2: use to do the probing, which is the scanning tunneling microscope,
• 7:05
  Speaker 2: or STM.
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  Speaker 3: Yes, the STM.
• 7:07
  Speaker 2: And the mechanics of this tool are just mind-bending to me.
• 7:10
  Speaker 2: They take an ultra-sharp metallic tip, and we are talking
• 7:14
  Speaker 2: sometimes tapering down to a single atom at its point.
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  Speaker 3: Literally one atom wide at the tip.
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  Speaker 2: Unbelievable.
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  Speaker 3: Right?
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  Speaker 2: And they bring it incredibly close to the cobaltocene molecule,
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  Speaker 2: like fractions of a nanometer close.
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  Speaker 3: Very, very close.
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  Speaker 2: They bring it so close that electrons can actually cross
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  Speaker 2: the empty vacuum gap between the tip and the molecule.
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  Speaker 3: Right. And this relies entirely on quantum tunneling.
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  Speaker 2: Because normally that shouldn't happen. No.
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  Speaker 3: In classical physics, an electron shouldn't be able to cross
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  Speaker 3: that empty space without a wire to travel along. The
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  Speaker 3: vacuum is a physical barrier.
• 7:48
  Speaker 2: Right.
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  Speaker 3: But in quantum mechanics, an electron isn't just a solid particle.
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  Speaker 3: It acts as a wave of probability.
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  Speaker 2: Okay, so instead of a baseball hitting a wall and
• 7:59
  Speaker 2: bouncing off, it's more like a.
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  Speaker 3: Like a sound wave passing through a wall.
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  Speaker 2: A sound wave, exactly.
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  Speaker 3: That is a much more accurate way to visualize it.
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  Speaker 3: The electron's probability cloud literally extends past the physical boundary
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  Speaker 3: of the microscope tip.
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  Speaker 2: It just bleeds over.
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  Speaker 3: Yes, it bleeds right into the space of the molecule.
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  Speaker 3: And if the energetic conditions are just right, the electron
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  Speaker 3: will simply materialize on the molecule, passing right through that barrier.
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  Speaker 2: That is wild.
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  Speaker 1: It is.
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  Speaker 3: And by carefully altering the energy of the electrons, they
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  Speaker 3: push across that gap, and then recording the resulting electrical current,
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  Speaker 3: the researchers map out a spectrum.
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  Speaker 2: And this is where we get back to those spikes
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  Speaker 2: on the graph that we mentioned earlier.
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  Speaker 3: Exactly.
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  Speaker 2: As they steadily sweep through different energy levels, a sudden
• 8:43
  Speaker 2: jump or a spike in the electrical current indicates that
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  Speaker 2: a specific quantum process was just triggered inside the molecule
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  Speaker 2: at that exact energy. Boom. Energy was absorbed, a state changed,
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  Speaker 2: and there is our signal.
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  Speaker 3: But, and this is the kicker, this brings us right
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  Speaker 3: back to the original problem.
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  Speaker 2: The orchestral noise?
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  Speaker 3: Yes. A single spike on that graph does not reveal
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  Speaker 3: the nature of the process. You have a massive cluster
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  Speaker 3: of different excitations happening in the same spectrum all overlapping
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  Speaker 3: each other.
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  Speaker 2: Just a bunch of vertical lines on a readout.
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  Speaker 3: Exactly.
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  Speaker 2: It's still just noise. So how did Dr. Banerjee and
• 9:18
  Speaker 2: his team actually decode this? Because just running the scanning
• 9:22
  Speaker 2: tunneling microscope clearly wasn't enough to distinguish the signals.
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  Speaker 3: No, it wasn't. They realized they had to layer their
• 9:28
  Speaker 3: observation methods to basically force the molecule to reveal its secrets. Okay.
• 9:33
  Speaker 3: So they combined two incredibly novel approaches simultaneously. First, they
• 9:38
  Speaker 3: dynamically moved electrons into and out of the molecule using
• 9:41
  Speaker 3: the microscope tip, altering its fundamental charge state on the fly.
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  Speaker 2: Right.
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  Speaker 3: But second, and crucially, they subjected the entire superconducting setup
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  Speaker 3: to an intense external magnetic field while they were tunneling
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  Speaker 3: those electrons.
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  Speaker 2: Okay, let's dig into the physics of that magnetic field,
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  Speaker 2: because that seems to be the real linchpin here.
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  Speaker 3: It absolutely is.
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  Speaker 2: Why does hitting the molecule with a huge magnet suddenly
• 10:05
  Speaker 2: help you categorize a completely ambiguous spike on a graph?
• 10:08
  Speaker 3: Well, what's fascinating here is it comes down to something
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  Speaker 3: called the Zeeman effect.
• 10:13
  Speaker 2: The Zeeman effect.
• 10:14
  Speaker 3: Yes. When you look at the different ways a molecule
• 10:17
  Speaker 3: can be excited... They operate on fundamentally different physical principles.
• 10:21
  Speaker 3: Take an electron spin, for example. Okay. An electron has
• 10:24
  Speaker 3: an intrinsic angular momentum, a spin, which effectively makes it
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  Speaker 3: a tiny magnetic dipole. It behaves exactly like a microscopic
• 10:33
  Speaker 3: compass needle.
• 10:34
  Speaker 2: So if it's a tiny magnet, it is inherently going
• 10:37
  Speaker 2: to react to an external magnetic force.
• 10:38
  Speaker 3: Exactly. When you introduce a strong external magnetic field, that
• 10:43
  Speaker 3: tiny compass needle wants to align with it. Makes sense.
• 10:46
  Speaker 3: So if you try to force that electron spin to
• 10:48
  Speaker 3: flip its orientation, pushing it against the magnetic field, it
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  Speaker 3: suddenly requires a different amount of energy than it did
• 10:55
  Speaker 3: when the field was turned off.
• 10:56
  Speaker 2: Oh, wow.
• 10:57
  Speaker 1: Yeah.
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  Speaker 3: So when the researchers applied the magnetic field, they watched
• 11:01
  Speaker 3: specific spikes on their spectrum physically shift their position on
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  Speaker 3: the graph.
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  Speaker 2: And that shift instantly told them, hey, this specific spike
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  Speaker 2: is a spin excitation?
• 11:09
  Speaker 3: Precisely.
• 11:10
  Speaker 2: Because the other types of excitations simply don't care about
• 11:13
  Speaker 2: the magnet at all?
• 11:14
  Speaker 3: They are completely indifferent to it. Consider a mechanical vibration
• 11:18
  Speaker 3: of the molecule.
• 11:18
  Speaker 2: Like it just physically shaking?
• 11:20
  Speaker 1: Right.
• 11:21
  Speaker 3: This is the actual atomic nuclei of the cobaltocene structure oscillating,
• 11:26
  Speaker 3: vibrating in place like a microscopic tuning fork. Atomic nuclei
• 11:31
  Speaker 3: are thousands of times heavier than electrons, and their vibrational
• 11:35
  Speaker 3: modes are dictated by the chemical bonds holding the molecule together,
• 11:38
  Speaker 3: not by magnetic dipoles.
• 11:41
  Speaker 2: So they ignore the magnet?
• 11:42
  Speaker 3: Completely. So when the massive magnetic field is turned on,
• 11:46
  Speaker 3: The energetic signature of that physical vibration doesn't change at all.
• 11:50
  Speaker 3: The spike on the graph stays perfectly stationary.
• 11:53
  Speaker 2: That is brilliant.
• 11:55
  Speaker 3: So by just watching which spikes shift under the magnet
• 11:58
  Speaker 3: and which stay perfectly still, they can instantly separate a
• 12:02
  Speaker 3: spin flip from a physical vibration.
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  Speaker 2: Exactly.
• 12:05
  Speaker 3: It cleanly separates them.
• 12:07
  Speaker 2: And there was a third behavior they were able to
• 12:09
  Speaker 2: isolate as well, right? An orbital hop.
• 12:12
  Speaker 3: Yeah, the orbital excitation is an entirely different beast. This
• 12:15
  Speaker 3: is when an electron physically changes its geometric energy lane.
• 12:19
  Speaker 2: Like switching tracks?
• 12:21
  Speaker 3: Yes. Jumping from one designated probability path around the molecule
• 12:25
  Speaker 3: to a totally different spatial configuration.
• 12:27
  Speaker 1: Wow.
• 12:28
  Speaker 3: Orbital hops require a different scale of energy, and they
• 12:31
  Speaker 3: respond distinctly to the dynamic injection of electrons moving in
• 12:35
  Speaker 3: and out of the system.
• 12:36
  Speaker 2: Right, that first novel approach you mentioned.
• 12:38
  Speaker 3: Exactly. So by combining the magnetic field data with the
• 12:42
  Speaker 3: dynamic charge shifting data, The chaotic noise separated into pure clarity.
• 12:48
  Speaker 2: It's like suddenly hearing the individual instruments.
• 12:50
  Speaker 1: Yes.
• 12:51
  Speaker 3: They isolated three distinct quantum events. A spin flip, a
• 12:56
  Speaker 3: molecular vibration, and an orbital hop.
• 13:00
  Speaker 2: So what used to look like identical, confusing jumps on
• 13:02
  Speaker 2: a graph are now categorized flawlessly.
• 13:05
  Speaker 3: Flawlessly.
• 13:06
  Speaker 2: But the researchers didn't stop at figuring out what the
• 13:08
  Speaker 2: molecule was doing. I mean, knowing the mechanism is a
• 13:11
  Speaker 2: massive leap forward. But they pushed the experiment a step
• 13:13
  Speaker 2: further to see exactly where these specific excitations were happening
• 13:18
  Speaker 2: across the physical structure of the single molecule. Right.
• 13:21
  Speaker 3: This moves the achievement from a triumph of data analysis
• 13:24
  Speaker 3: into a triumph of spatial mapping. Yeah. Because they were
• 13:27
  Speaker 3: using a scanning tunneling microscope, they were just probing the
• 13:31
  Speaker 3: molecule from a single static angle. they could physically move
• 13:35
  Speaker 3: that ultra-sharp metallic tip across the topography of the cobaltocene molecule,
• 13:40
  Speaker 3: scanning it point by point with submolecular resolution.
• 13:44
  Speaker 2: Which means they are essentially mapping the spatial distribution of
• 13:47
  Speaker 2: the probability of excitation.
• 13:49
  Speaker 3: That's a mouthful, but yes.
• 13:51
  Speaker 2: Here's where it gets really interesting, though. To visualize this,
• 13:54
  Speaker 2: they aren't looking at a physical photograph of the molecule.
• 13:57
  Speaker 3: No, not at all.
• 13:58
  Speaker 2: They're creating a highly precise topographical heat map. So they
• 14:03
  Speaker 2: can say with absolute certainty, OK, the electron spin flip
• 14:06
  Speaker 2: has a high probability of occurring over on this specific
• 14:09
  Speaker 2: edge of the carbon ring, while the orbital hop is
• 14:11
  Speaker 2: heavily localized dead center over the cobalt atom.
• 14:15
  Speaker 3: Exactly. They map the likelihood of these events happening at
• 14:17
  Speaker 3: very specific coordinates. But mapping the topography of quantum probability
• 14:22
  Speaker 3: at a submolecular scale is incredibly prone to error.
• 14:26
  Speaker 2: Because it's so delicate.
• 14:27
  Speaker 3: Extremely delicate. You are dealing with wave functions. So to
• 14:31
  Speaker 3: prove they weren't just seeing experimental artifacts, you know, ghosts
• 14:34
  Speaker 3: in the machine, they had to validate their physical maps
• 14:37
  Speaker 3: with rigorous mathematical modeling. Oh, right.
• 14:41
  Speaker 2: Because seeing the data is one thing, but in physics,
• 14:43
  Speaker 2: the math has to back it up.
• 14:44
  Speaker 3: The math must predict the reality.
• 14:46
  Speaker 2: And to do that, they turned to a mathematical framework
• 14:49
  Speaker 2: called time-dependent density functional theory, or TDDFT.
• 14:53
  Speaker 3: Yes.
• 14:54
  Speaker 2: Which sounds pretty intimidating.
• 14:56
  Speaker 3: It is, mathematically speaking.
• 14:57
  Speaker 2: But it is effectively the forensic mathematics needed to back
• 15:01
  Speaker 2: up the physical fingerprints they found with the microscope.
• 15:03
  Speaker 3: That's exactly it. So standard density functional theory is basically
• 15:07
  Speaker 3: a computational workhorse in physics. Attempting to calculate the exact
• 15:11
  Speaker 3: wave function of dozens of interacting electrons simultaneously requires impossible
• 15:16
  Speaker 3: amounts of computing power.
• 15:18
  Speaker 2: Because it's a many-body problem again. Right.
• 15:20
  Speaker 3: So DFT simplifies this by modeling the system as a
• 15:24
  Speaker 3: single three-dimensional cloud of electron density.
• 15:27
  Speaker 2: Okay, that makes sense.
• 15:28
  Speaker 3: But standard DFT is primarily used to look at a
• 15:30
  Speaker 3: system in its resting ground state.
• 15:33
  Speaker 2: Which doesn't help us because we are looking at a
• 15:35
  Speaker 2: molecule that is actively being excited and blasted with electrons.
• 15:38
  Speaker 2: It's not resting.
• 15:39
  Speaker 3: Exactly. That is where the time-dependent extension comes in. TDDFT
• 15:45
  Speaker 3: introduces the variable of time, allowing physicists to mathematically simulate
• 15:50
  Speaker 3: how that 3D electron cloud sloshes, shifts, and responds to
• 15:54
  Speaker 3: an external perturbation.
• 15:55
  Speaker 2: In this case, the tunneling electrons from the microscope tip. Right.
• 15:59
  Speaker 3: It is a massive computational effort to simulate these exact
• 16:03
  Speaker 3: interacting probabilistic waves as they are actively pushed out of equilibrium.
• 16:08
  Speaker 2: So they essentially build a perfect mathematical simulation of their
• 16:12
  Speaker 2: ultra-cold magnetic microscope setup inside a computer.
• 16:15
  Speaker 3: They did.
• 16:16
  Speaker 2: And the real triumph here is that when they ran
• 16:18
  Speaker 2: those elaborate TDDFT calculations, they The mathematical predictions perfectly mirrored
• 16:24
  Speaker 2: the spatial heat maps they had generated physically.
• 16:26
  Speaker 3: Down to the smallest detail.
• 16:28
  Speaker 2: The pure theory and the physical measurement aligned beautifully.
• 16:31
  Speaker 3: It provided the absolute ultimate confirmation of their assignment of
• 16:34
  Speaker 3: the measurement signals. And the physics community recognized the weight
• 16:38
  Speaker 3: of this immediately.
• 16:39
  Speaker 2: I bet.
• 16:40
  Speaker 3: Yeah. The findings were published in the journal Physical Review Letters,
• 16:43
  Speaker 3: which is one of the most prestigious physics journals in
• 16:46
  Speaker 3: the world. And it was even specifically highlighted as an
• 16:49
  Speaker 3: editor's suggestion.
• 16:51
  Speaker 2: Wow.
• 16:51
  Speaker 3: It is a major foundational breakthrough.
• 16:55
  Speaker 2: Which brings us to the ultimate question for you listening.
• 16:58
  Speaker 2: We've spent this time unraveling extreme quantum mechanics, superconducting lead,
• 17:02
  Speaker 2: the Zeeman effect, all of this stuff.
• 17:04
  Speaker 3: A lot of heavy physics.
• 17:05
  Speaker 2: Right. It is brilliant science. But why does the specific
• 17:08
  Speaker 2: ability to distinguish between a spin flip, a vibration and
• 17:13
  Speaker 2: an orbital hot matter outside the laboratory?
• 17:16
  Speaker 3: Well, if we connect this to the bigger picture, it
• 17:18
  Speaker 3: matters because of the inevitable trajectory of computational technology.
• 17:22
  Speaker 2: Okay.
• 17:23
  Speaker 3: Dr. Alexander Weissman, a co-author on this study, highlighted a
• 17:27
  Speaker 3: really fundamental reality. Molecules are inherently quantum systems. They operate
• 17:33
  Speaker 3: natively on the rules of quantum mechanics. For decades, the
• 17:37
  Speaker 3: tech industry has been desperately trying to build viable quantum computers,
• 17:41
  Speaker 3: machines that can leverage quantum superposition to You know, model
• 17:45
  Speaker 3: climate change, discover complex drugs instantly, or crack advanced encryption
• 17:49
  Speaker 3: in seconds.
• 17:50
  Speaker 2: But the hardware required to build those computers, the qubits,
• 17:54
  Speaker 2: are incredibly unstable and difficult to manufacture.
• 17:58
  Speaker 3: Very difficult. But if we want to use individual molecules
• 18:01
  Speaker 3: as the native building blocks, the qubits of future quantum computers,
• 18:06
  Speaker 3: we absolutely must be able to control their states.
• 18:08
  Speaker 2: So what does this all mean practically?
• 18:11
  Speaker 3: Think about a standard silicon computer. If your software sends
• 18:15
  Speaker 3: an electrical signal to flip a bit from a zero
• 18:17
  Speaker 3: to a one, you know exactly what is happening. There
• 18:20
  Speaker 3: is a predictable, flawless relationship between the action and the
• 18:23
  Speaker 3: state of the hardware.
• 18:24
  Speaker 2: Right. You type a key, a letter appears.
• 18:27
  Speaker 3: Exactly. But with a molecule, if you try to write
• 18:30
  Speaker 3: data to it by injecting energy, and you can't tell
• 18:32
  Speaker 3: if you just flipped an electron spin, caused a physical
• 18:36
  Speaker 3: atomic vibration, or made an electron hop an orbital.
• 18:39
  Speaker 2: Your computer's entirely blind.
• 18:41
  Speaker 3: Exactly. If your right operation accidentally causes a mechanical vibration
• 18:45
  Speaker 3: instead of an orbital hop, that energy just diffuses as heat.
• 18:49
  Speaker 2: And your data is gone.
• 18:50
  Speaker 3: Your quantum information is instantly destroyed. So distinguishing these distinct
• 18:56
  Speaker 3: quantum excitations flawlessly is the absolute non-negotiable prerequisite for utilizing
• 19:01
  Speaker 3: molecules as hardware.
• 19:03
  Speaker 2: So the work happening at Kiel University, specifically at Kinsis,
• 19:07
  Speaker 2: their Kiel Nano Surface and Interface Science focus area, is
• 19:10
  Speaker 2: literally writing the instruction manual for the quantum hardware of
• 19:14
  Speaker 2: the next century.
• 19:15
  Speaker 3: It really is. Dr. Weissman expressed deep hope that Keeley
• 19:19
  Speaker 3: University continues to champion this promising field. And it is
• 19:23
  Speaker 3: incredibly clear why. They aren't just observing a phenomenon anymore.
• 19:28
  Speaker 2: They are creating the roadmap for control.
• 19:30
  Speaker 3: It is the critical transition from being a passive observer
• 19:33
  Speaker 3: of quantum chaos to an active engineer of quantum systems.
• 19:38
  Speaker 3: We can finally read the exact nature of the energy
• 19:41
  Speaker 3: and map exactly where inside the molecular structure that energy manifests.
• 19:45
  Speaker 2: It is an incredible technological leap when you look back
• 19:48
  Speaker 2: at where we started today. I mean, we began with
• 19:50
  Speaker 2: models that failed us and signals that were just an ambiguous,
• 19:54
  Speaker 2: overlapping mess of acoustic noise.
• 19:56
  Speaker 3: We were listening to a dense chord with no idea
• 19:58
  Speaker 3: what instruments were playing. Right.
• 20:00
  Speaker 2: Then we dropped the temperature to near absolute zero, utilizing
• 20:04
  Speaker 2: the precise energy gap of a macroscopic superconducting state. We
• 20:08
  Speaker 2: brought in a microscopic needle and utilized the probabilistic wave
• 20:11
  Speaker 2: nature of quantum tunneling to inject electrons, and introduced a
• 20:15
  Speaker 2: massive magnetic field to tease apart the spin states from
• 20:18
  Speaker 2: the atomic vibrations.
• 20:19
  Speaker 3: And through that layered extreme engineering, the chaos finally separated
• 20:24
  Speaker 3: into distinct mathematically verifiable signals. The physical spatial mapping aligned
• 20:29
  Speaker 3: flawlessly with the time-dependent density functional theory calculations.
• 20:33
  Speaker 2: We basically took a room that has been dark since
• 20:35
  Speaker 2: the dawn of modern physics, and we didn't just turn
• 20:38
  Speaker 2: on the lights. We mapped every inch of the floor plan.
• 20:42
  Speaker 3: We really did. But, you know, the implications extend far
• 20:45
  Speaker 3: beyond just building a faster computer.
• 20:48
  Speaker 2: How so?
• 20:49
  Speaker 3: This level of granular submolecular control raises a really profound
• 20:53
  Speaker 3: question about the future of human engineering. If scientists today
• 20:58
  Speaker 3: can flawlessly read and map the precise physical vibrations and
• 21:02
  Speaker 3: electron hops inside a single molecule.
• 21:04
  Speaker 2: Yeah.
• 21:05
  Speaker 3: How long will it be before we begin choreographing those
• 21:07
  Speaker 3: states to interface directly with biology? Oh, wow. Think about it.
• 21:12
  Speaker 3: Molecules are the fundamental building blocks of living tissue. If
• 21:15
  Speaker 3: we can achieve true computational control over individual molecules, we
• 21:20
  Speaker 3: are looking at a future where programmable quantum logic could
• 21:23
  Speaker 3: be integrated directly into organic chemistry.
• 21:26
  Speaker 2: That is wild.
• 21:28
  Speaker 3: Imagine molecular-scale quantum sensors safely deployed inside living cells. repairing
• 21:33
  Speaker 3: DNA or mapping disease at the exact quantum level where
• 21:37
  Speaker 3: those chemical reactions occur.
• 21:39
  Speaker 2: That is a staggering thought to consider. We aren't just
• 21:42
  Speaker 2: moving toward better technology. We are moving toward a total
• 21:46
  Speaker 2: convergence of quantum physics, computation, and biology.
• 21:50
  Speaker 3: Exactly. We are stepping out of the audience and taking
• 21:54
  Speaker 3: our place as the conductor of the microscopic symphony.
• 21:57
  Speaker 2: I love that. Keep questioning the world around you, no
• 22:00
  Speaker 2: matter how small it might seem. There is always more
• 22:03
  Speaker 2: hiding in the invisible details.