Speaker 1: Welcome to the qure side Quantum Physics Podcast, an exploration
Speaker 1: of the fundamental structure of reality where quantum laws govern matter, energy,
Speaker 1: and information. Here, uncertainty is a feature, not a flaw,
Speaker 1: and understanding begins with the smallest scales.
Speaker 2: Imagine you're holding a computer processor right like, right in
Speaker 2: the palm of your hand, and this chip has the
Speaker 2: power to cure complex genetic diseases in a matter of days, or.
Speaker 3: Unravel the most secure cryptographic codes on Earth in seconds.
Speaker 2: Exactly. The potential is literally sitting right there. But uh,
Speaker 2: if you actually look at it, and I mean literally,
Speaker 2: if a single stray particle of ambient light bounces off it,
Speaker 2: the whole thing shatters.
Speaker 3: Yeah, Or if the temperature in the room changes by
Speaker 3: even a fraction of a degree, the calculation is just
Speaker 3: ruined instantly.
Speaker 2: It's so frustrating. I mean, that is the almost absurd
Speaker 2: reality of quantum computing today. We have this theoretical magic,
Speaker 2: this unimaginable computational power, but it's trapped.
Speaker 3: Right, trapped inside some of the most delicate, fragile hardware
Speaker 3: ever conceived.
Speaker 2: Right, And to keep these machines running, we have to
Speaker 2: lock them inside these massive dilution refrigerators cooled to what
Speaker 2: fractions of a degree above absolute zero.
Speaker 3: It's a colder than deep space, which is just.
Speaker 2: It's an unsustainable brute force way to protect something delicate.
Speaker 2: But researchers at Chalmers University of Technology in Sweden they
Speaker 2: proposed a completely different approach back in late twenty twenty five.
Speaker 3: They did, Yeah, it's a fascinating pivot.
Speaker 2: Instead of building a bigger, colder shield around the fragile parts,
Speaker 2: they realized we could fundamentally redesign the atoms themselves by
Speaker 2: making them.
Speaker 3: Giant, which sounds like science fiction, I know, But the
Speaker 3: problem they were trying to solve is honestly the single
Speaker 3: biggest roadblock in modern fisths decoherence, right exactly, decoherence in
Speaker 3: the quantum realm. That is the ultimate enemy. And to
Speaker 3: really grasp why this new Chalmers architecture is such a
Speaker 3: radical shift, kind of have to look at why these
Speaker 3: systems are so painfully fragile in the first place.
Speaker 2: Well, let's break that down. Because a normal computer bit
Speaker 2: is simple, right, It's like a coin sitting on a table.
Speaker 2: It's either heads or its tails, a one.
Speaker 3: Or a zero, right, very binary, very stable.
Speaker 2: Yeah, and it takes a lot of force to physically
Speaker 2: flip that coin over, which is why your laptop doesn't
Speaker 2: crash every time someone turns on a light switch. But
Speaker 2: the fundamental building block of a quantum computer, equibit, operates
Speaker 2: entirely differently. It relies on a state called superposition.
Speaker 3: So if a normal bit is a coin sitting flat
Speaker 3: on a table, a quibit is a coin spinning rapidly
Speaker 3: in the air, just a blur exactly while it's spinning.
Speaker 3: It isn't strictly heads or tails. It exists as this
Speaker 3: blur of both probabilities simultaneously, and this superposition is what
Speaker 3: allows a quantum computer to process multiple possibilities at the
Speaker 3: exact same time rather than sequentially.
Speaker 1: Wow.
Speaker 2: Okay. And then there's the other crucial element, which is entanglement.
Speaker 3: Right. You can link two or more of these spinning
Speaker 3: coins together so deeply that if you interact with one,
Speaker 3: the others instantly react.
Speaker 2: No matter how far apart they are, right exactly.
Speaker 3: Einstein famously called it scooky action at a distance. It
Speaker 3: is the absolute foundation of complex parallel quantum math.
Speaker 2: But keeping a coin spinning perfectly in the air requires
Speaker 2: well absolute stillness, perpet isolation, yes, any environmental noise like heat,
Speaker 2: which is really just the vibration of atoms where electromagnetic
Speaker 2: static or that stray Photona mentioned. It acts like a
Speaker 2: hand slapping the spinning coin down onto the table.
Speaker 3: It forces the quibut to pick heads or tails.
Speaker 2: Right, the superposition collapses, the entanglement breaks, and the calculation
Speaker 2: is completely ruined. That's decoherence.
Speaker 3: And the classical approach to stopping decoherence is well, it's
Speaker 3: essentially trying to isolate the system from the entire universe.
Speaker 2: Those massive refrigerators.
Speaker 3: Yeah, we cool the processors to it near absolute zero,
Speaker 3: and we also use incredibly heavy error correcting codes.
Speaker 2: What does that actually mean in practice?
Speaker 3: It means building hundreds of physical backup quibots just to
Speaker 3: keep one single working quibot stable. It's incredibly inefficient.
Speaker 2: It makes me think of imagine building a delicate house
Speaker 2: of cards in the middle of a windstorm.
Speaker 3: That's a good way to put it.
Speaker 2: The traditional engineering solution has basically been to try and
Speaker 2: build a billion dollar, perfectly sealed, climate controlled dome over the.
Speaker 3: Cards, right, which works for a handful of cards. Yeah,
Speaker 3: But if you want to scale up to millions of
Speaker 3: quibots to build a truly powerful supercomputer.
Speaker 2: The hardware overhead becomes impossible. The energy required to power
Speaker 2: millions of domes, it's just astronomical, exactly.
Speaker 3: So the Chalmers team shifted the entire paradigm. They asked
Speaker 3: a different question.
Speaker 2: Instead of building a better dome, what if we fundamentally
Speaker 2: redesign the cards so they can't be blown over?
Speaker 3: Precisely, they asked, what if we design an entirely new
Speaker 3: kind of instrument, one that uses its own acoustics to
Speaker 3: cancel out the noise. And their starting point for this
Speaker 3: was artificial quantum emitters.
Speaker 2: Which scientists have been studying for over a decade now, right, yeah,
Speaker 2: quite a while. We should probably clarify when we say
Speaker 2: atom in this context. We aren't talking about something you'd
Speaker 2: find naturally on the periodic table.
Speaker 3: Oh, definitely not. These are manufactured components. In practical terms,
Speaker 3: they are often tiny superconducting circuits engineered on a chip
Speaker 3: to behave identically to an atom.
Speaker 2: So they aren't real atoms, but they act like them, right, They.
Speaker 3: Have discrete energy levels. They absorb and emit microwave photons,
Speaker 3: just like a natural atom absorbs light and they obey
Speaker 3: all the bizarre rules of quantum mechanics. Okay, got it.
Speaker 3: But a natural atom is incredibly small. When it interacts
Speaker 3: with the light or sound in its environment, it acts
Speaker 3: like a tiny microphone picking up audio at one single
Speaker 3: microscopic point.
Speaker 2: Oh okay, so it's very localized exactly.
Speaker 3: But a giant atom connects to its environment in a
Speaker 3: completely different way. It is engineered to couple to a waveguide.
Speaker 2: Which is basically a channel carrying microwavelight.
Speaker 3: Right, yes, exactly, But it couples to that waveguide at
Speaker 3: multiple spatially separated points. Wow, okay, And because it spans
Speaker 3: across these multiple connection points, the artificial atom can be
Speaker 3: giant relative to the wavelength of the light it interacts with.
Speaker 3: We are talking up to millimeters in size.
Speaker 2: Wait, millimeters. So you could literally hold a single quantum
Speaker 2: component in your hand and see it with your naked eye.
Speaker 3: You could, which completely defies our everyday intuition about quantum mechanics.
Speaker 2: Yeah, it's supposed to be invisible.
Speaker 3: Exactly, And those multiple connection points, they're the secret to
Speaker 3: its stability. In physics, we call the resulting effect self interference.
Speaker 2: Okay, self interference. So Keeping with our acoustic analogy, imagine
Speaker 2: you're yelling into a canyon, but instead of the sound
Speaker 2: just drifting away, the canyon is design so the echo
Speaker 2: bounces back perfectly right, because.
Speaker 3: The giant atom interacts with the wave guide at multiple
Speaker 3: separated points. The quantum wave it emits at the first point,
Speaker 3: travels down the line and actually interacts with the atom
Speaker 3: itself again at the second.
Speaker 2: Point, So it literally hears its own echo before it
Speaker 2: finishes speaking.
Speaker 3: It does, and that echo isn't just a quirky acoustic trick.
Speaker 3: It's a profound protective mechanism. How So, by engineering the
Speaker 3: exact spacing of those connection points, physicists can ensure the
Speaker 3: returning wave creates destructive interference. It acts as a shield.
Speaker 2: Oh wow, So it actively suppresses the rate at which
Speaker 2: the atom decays.
Speaker 3: Exactly, It traps the fragile quantum information inside, protecting it
Speaker 3: from the chaotic thermal noise outside. In technical terms, this
Speaker 3: creates non Markovian dynamics.
Speaker 2: Non Markovian which simply means the system has a memory, right.
Speaker 3: Yes, exactly. The standard atom is entirely stuck in the
Speaker 3: present moment. It reacts blindly to whatever.
Speaker 2: Hits it, but a giant atom because of this continuous
Speaker 2: loop of self interference. It's constantly influenced by its own
Speaker 2: past emissions.
Speaker 3: It uses its own history as a stabilizing anchor.
Speaker 2: That is incredible. Okay, so the giant atom gives us
Speaker 2: built in resistance to environmental noise. But a single stable
Speaker 2: atom is still just a calculator.
Speaker 3: Right, It's not a supercomputer.
Speaker 2: To perform the complex math that quantum computing promises, you
Speaker 2: need thousands or millions of these units working together seamlessly,
Speaker 2: and controlling millions of giant atoms presents an entirely new
Speaker 2: logistical nightmare.
Speaker 3: Oh absolutely, Imagine trying to conduct an orchestra of a
Speaker 3: million musicians, but instead of waving a baton, you have
Speaker 3: to write a separate, highly complex set of individual instructions
Speaker 3: for every single person, for every single note they play.
Speaker 2: The sheer volume of wiring, the crosstalk between the cables,
Speaker 2: the interference, it just becomes an unmanageable mess, which.
Speaker 3: Brings us to the second innovation required for this architecture,
Speaker 3: the super.
Speaker 2: Anim the super adom. What exactly is.
Speaker 3: That superatum is a collective quantum system. You take multiple atoms,
Speaker 3: they're natural or artificial, and you entangle them internally so
Speaker 3: intensely that they completely lose their individual identities.
Speaker 2: WHOA, so they just merge.
Speaker 3: They merge, they become a single, larger super entity sharing
Speaker 3: the exact same quantum states.
Speaker 2: So our orchestra section isn't fifty individual violins anymore. They're
Speaker 2: so perfectly linked that they function as one giant, unified
Speaker 2: instrument exactly.
Speaker 3: And when an external force interacts with them, it doesn't
Speaker 3: hit violin A or violin B. It interacts with the
Speaker 3: entire collective at once.
Speaker 2: I see.
Speaker 3: So you can interest the whole group with a single command,
Speaker 3: which drastically simplifies the control systems needed to operate the computer.
Speaker 2: Okay, so we have two incredibly powerful concepts here. The
Speaker 2: giant atom provides the acoustic shield, the self interference that
Speaker 2: protects against noise, and the super atom provides the simplicity
Speaker 2: allowing us to control a complex group as a single entity.
Speaker 3: Yes, and the obvious yet incredibly difficult next step is
Speaker 3: what happens when you fuse them together.
Speaker 2: So that's the breakthrough from late twenty twenty five published
Speaker 2: in Physical Reviewer.
Speaker 3: That's the one led by a team including leydu jin Wang,
Speaker 3: Anton Friskcocum, and Janine Splitstozer. They mapped out the mathematics
Speaker 3: to assemble the hybrid giant superatom.
Speaker 2: Okay, wait, hold on, I'm struggling with the logic here.
Speaker 3: Okay, what's the issue.
Speaker 2: Well, we just established that quibits are unbelievably delicate, right
Speaker 2: like house of cards. Yes, and now the proposal is
Speaker 2: to take a bunch of them, entangle them into this
Speaker 2: massive superatom, and then poke more holes in the system
Speaker 2: to connect them to the environment in multiple separate places
Speaker 2: to make them giants.
Speaker 3: I see where you're going with this.
Speaker 2: But doesn't adding all that internal complexity and exposing the
Speaker 2: system to the environment in more places just invite more noise.
Speaker 2: It feels like building a submarine and then drilling extra
Speaker 2: holes in the hall to make it safer.
Speaker 3: It does sound like a paradox, but that is the
Speaker 3: exact problem that Cholmer's team had to solve, and they
Speaker 3: did it through the mathematics of something called dressed interference.
Speaker 2: Dressed interference.
Speaker 3: Yeah, when you strongly couple atoms together to form a superatom,
Speaker 3: they don't just sit next to each other. Their individual
Speaker 3: energy levels shift and merge. They become dressed states. Okay,
Speaker 3: think of it like taking two tuning forks and pressing
Speaker 3: them physically together. If you strike them, they no longer
Speaker 3: ring with their individual isolated notes.
Speaker 2: The physical connection forces them to vibrate together exactly.
Speaker 3: It creates an entirely new blended frequency.
Speaker 2: Okay, So the complex internal entanglement actually creates a highly
Speaker 2: specific custom frequency.
Speaker 3: And that custom frequency is the key. Remember the self
Speaker 3: interference of the giant atom the protective echo in a
Speaker 3: giant superatom. That echo isn't just bouncing off a single
Speaker 3: atom anymore. It is interacting with this complex blended frequency
Speaker 3: of the dressed collective. Oh and what the team discovered
Speaker 3: is that this internal complexity is actually mathematically perfect. By
Speaker 3: carefully tuning the spacing of the connection points and the
Speaker 3: strength of how the atom are linked, the researchers achieved
Speaker 3: programmable directional control over the interference.
Speaker 2: So the complexity of the superatom essentially fine tunes the
Speaker 2: protective echo of the giant atom.
Speaker 3: It functions almost exactly like active noise canceling headphones, but
Speaker 3: operating natively at the quantum level across an entire collective
Speaker 3: of atoms.
Speaker 2: Because noise canceling headphones don't just block sound, they listen
Speaker 2: to the ambient noise and generate a perfectly inverted wave
Speaker 2: to cancel it out exactly.
Speaker 3: The giant super atom uses its dressed interference to provide
Speaker 3: the exact mathematical degrees of freedom needed to cancel out
Speaker 3: environmental static. This allows the system to perform what the
Speaker 3: researchers call decoherence free transfers of entangled.
Speaker 2: States ecoherence free. That's huge. That is the defining transition
Speaker 2: point for this technology, isn't it?
Speaker 3: It really is. We aren't just trying to cram more
Speaker 3: fragile components into a freezing cold vacuum chamber and hoping
Speaker 3: they survive. We are engineering a smart physics based stability
Speaker 3: directly into the foundation.
Speaker 2: Which means this isn't just abstract whiteboard math. I mean,
Speaker 2: if you're waiting for the day when quantum computing actually
Speaker 2: models a new life saving drug or protects your personal
Speaker 2: data with unbreakable cryptography, this architecture is the blueprint that
Speaker 2: gets us out of a lab.
Speaker 3: Yes, it outlines several massive practical advantages for engineers trying
Speaker 3: to build these.
Speaker 2: Machines, decoherence suppression being the first one. Obviously, naturally, the.
Speaker 3: Self interference provides a literal form of quantum memory, protecting
Speaker 3: the information inherently. The system is vastly less sensitive to
Speaker 3: thermal fluctuations.
Speaker 2: So we might still need refrigeration, but the hardware inside
Speaker 2: won't be so prone to catastrophic crashes every time a
Speaker 2: stray particle hits it.
Speaker 3: Exactly, and this inherent protection leads directly into a massive
Speaker 3: advantage for how the computer actually calculates. The giant superatom
Speaker 3: makes it significantly more efficient to generate, transfer and maintain entanglement.
Speaker 2: Because instead of painfully trying to force isolated, fragile quibbits
Speaker 2: to talk to each other one by one, the system
Speaker 2: manages entanglement collectively and robustly.
Speaker 3: Right. And another major benefit is that the physical footprint
Speaker 3: of the processor shrinks dramatically. Leydu, one of the lead researchers,
Speaker 3: pointed out how crucial this is.
Speaker 2: How much does it shrink well?
Speaker 3: A giant super atom allows quantum information from multiple quibbuts
Speaker 3: to be stored and controlled within one unit. This completely
Speaker 3: bypasses the need for the dense, incredibly complex surrounding circuitry
Speaker 3: we currently use.
Speaker 2: Oh right, because you no longer need a unique, perfectly
Speaker 2: isolated wire for every single quibit.
Speaker 3: Exactly, the wiring gets simpler, and the whole system becomes
Speaker 3: infinitely easier to scale up from a few dozen quibuts
Speaker 3: to the millions we need for commercial applications.
Speaker 2: And it doesn't just improve what we already know how
Speaker 2: to do right, it unlocks entirely new capabilities. I was
Speaker 2: looking at Janine Splittstos's work on the team and they
Speaker 2: realize the architecture allows for something called state selective chiral emission.
Speaker 3: Yes, state selective chiral emission. It sounds complicated, but chiral
Speaker 3: emission simply means the giant super atom can choose a
Speaker 3: direction like left or right, right, it can send its
Speaker 3: quantum information down the waveguide to the left or to
Speaker 3: the right, and state selective means it makes that directional
Speaker 3: choice dynamically based on its own internal quantum state.
Speaker 2: That's like a built in traffic cop for quantum information.
Speaker 3: That's exactly what it is.
Speaker 2: Which is crucial because if we are going to build
Speaker 2: a quantum Internet, a global network where information is shared
Speaker 2: instantly and securely, we need an efficient way to route
Speaker 2: data over long distances without destorying it.
Speaker 3: And the giant superadom provides that routing mechanism. Naturally, we
Speaker 3: wouldn't need a massive, separate network of fragile quantum switches
Speaker 3: to direct the traffic. The emitter itself acts as the switch.
Speaker 2: That's brilliant.
Speaker 3: Anton Friskoccum, another key researcher noted that because the system
Speaker 3: has a memory of its past interactions, it isn't just
Speaker 3: reacting blindly. It adapts its routing based on its history.
Speaker 2: It's just wild to think about. The theoretical heavy lifting
Speaker 2: is basically complete. The math works, and because giant atoms
Speaker 2: have already been success fully demonstrated in labs using these
Speaker 2: superconducting circuits, the pathway to physically building a giant super
Speaker 2: atom is really clear.
Speaker 3: We are definitely moving from physics to engineering.
Speaker 2: We are finally leaving behind the era of building massive,
Speaker 2: impossible domes to protect fragile spinning cards. By leaning into
Speaker 2: the strangest parts of quantum mechanics, using non local coupling,
Speaker 2: memory effects and dressed interference, we are literally learning to
Speaker 2: use the noise against itself.
Speaker 3: Is a profoundly elegant, fault tolerant solution. We are forcing
Speaker 3: the system to actively protect itself It.
Speaker 2: Completely changes the timeline for when this technology will actually
Speaker 2: arrive in our everyday lives. But it also leaves us
Speaker 2: with a truly bizarre philosophical reality to consider. Also, well,
Speaker 2: think about it. For a century, we've been taught that
Speaker 2: the spooky rules of quantum mechanics, like superposition, entanglement, atoms
Speaker 2: being in two places at once. All that was supposed
Speaker 2: to only apply to the invisible subatomic.
Speaker 3: World, right the microscopic realm.
Speaker 2: The quantum realm was supposed to to be completely disconnected
Speaker 2: from our everyday classical reality. But if engineers are successfully
Speaker 2: building these artificial giant quantum systems, super entities that are
Speaker 2: millimeters wide, that you can hold in your hand and
Speaker 2: look at without a microscope, and that dynamically adapt based
Speaker 2: on a memory of their past interactions, it blurs the
Speaker 2: line exactly where exactly does the weird invisible quantum world
Speaker 2: end and our everyday classical reality begin. If we can
Speaker 2: literally see a quantum component functioning on a desk in
Speaker 2: front of us, maybe the invisible world is finally bleeding
Speaker 2: into ours