All interesting physics is decentralized and local. If there was a central algorithm deciding what physics is allowed, we wouldn't have the enormous diversity and beauty of the universe emerging out of something like two dozen fundamental physical constants.

I think this decentralized nature is also important when trying to understand physical systems. When we came up with our definition of topological order based on error correction (https://doi.org/10.1103/PhysRevB.106.085143), it was absolutely crucial to use a decentralized algorithm and not a centralized one where you feed in the positions of all errors at once. It's the fediverse approach to error correction, if you like.

#physics #condensedmatter #condmat #fediverse

It seems like the basic building blocks of a topological quantum computer were demonstrated experimentally for the first time.

https://arxiv.org/abs/2601.20956

The promise of topological quantum computer – which would be resistant to errors because it would encode quantum information using trajectories of weird “quasiparticles” called anyons – is one of the main motivations why people investigate topological orders like fractional quantum Hall effect or spin liquids. The catch about this study is that, as far as I understand, it lacks the required stability, which arises from the fact that the topological order is exhibited by the ground state of the system (lowest energy), and the anyons are lowest excitations (lowest energies above the ground state). Here, as far as I understand, the topologically ordered state was created inside a quantum computer, with no reference to energy. Still, this is one step closer to realizing topological quantum computation. Also, the study uses quantum gates based both on anyon braiding – “winding” their trajectories around each other – and “fusion”, i.e. merging anyons with each other. I was not aware you can use fusion in this way.

#science #physics #quantum #CondensedMatter #CondMat #QuantumComputing #TopologicalOrder #anyons

I am still alive, and there are big news for the project – news that are over one month overdue, but I was so focused on writing grant proposals that I couldn’t find time to write about it. Long story short: we finished the preprint of our spin liquid paper (https://arxiv.org/pdf/2512.05630). This work originated much before I came to Darrick Chang’s group, thus I am only a third author, but I did my part within the QUINTO project.

What is it about? Basically, atoms can make photons interacting with each other. In general, the interaction of many simple objects can lead to unusual, counterintuitive behavior. For example, many interacting electrons can form fractional quantum Hall states, and many interacting spins can form spin liquids – both being complicated quantum states, whose unusual properties manifest themselves with emergence of “quasiparticles” – objects that behave like individual particles, although in reality they are collective states of many particles. These quasiparticles can behave unlike any elementary particle found in nature – for example, they can have a fraction of single electron charge, and be neither bosons nor fermions but “anyons”. In the paper, we ask: can we observe similar effects with atoms and light?

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#physics #science #quantum #CondMat #CondensedMatter #QuantumOptics #ColdAtoms #AtomicPhysics

⭐ Promising new superconducting material discovered with the help of AI

https://phys.org/news/2025-12-superconducting-material-ai.html

#materials #electronics #superconductivity #condmat #physics #ai

Topologically ordered states of matter are characterized by fascinating non-local quantum correlations in the many-body wave function. However, deciding whether a quantum state is topologically ordered or not is extremely difficult. A large part of the problem is that so far, signatures like the topological entanglement entropy could not be efficiently computed.

We are happy to present a framework for the computation of topological order that provides an exponential speedup over existing methods: https://dx.doi.org/10.1088/1367-2630/ae3598

#quantum #physics #condensedmatter #condmat

⚡ Anomalous electronic state opens pathway to room-temperature superconductivity

https://phys.org/news/2025-11-anomalous-electronic-state-pathway-room.html

#superconductivity #materials #condmat #physics #solidstate #technology #electronics

◍ Diverse particles form identical geometric patterns when confined, model reveals

https://phys.org/news/2025-11-diverse-particles-identical-geometric-patterns.html

#materials #physics #condmat #phasetransition #granular

⚡ Pioneering recipe for conductive plastics paves way for human bodies to go online

https://techxplore.com/news/2025-09-recipe-plastics-paves-human-bodies.html

#materials #plastics #condmat #chemistry #bionics

🧊 Atomic-level engineering enables new alloys that won't break in extreme cold

https://phys.org/news/2025-09-atomic-enables-alloys-wont-extreme.html

#science #metallurgy #alloy #materials #cold #condmat #engineering #research

🪶 3D-printed superconductor achieves record performance with soft matter approach

https://phys.org/news/2025-08-3d-superconductor-soft-approach.html

#cornell #condmat #physics #engineering #electronics #materials #superconductor

💎 Scientists design superdiamonds with theoretically predicted hexagonal crystal structure

https://phys.org/news/2025-08-scientists-superdiamonds-theoretically-hexagonal-crystal.html

#condmat #materials #diamond #crystals #physics #chemistry

🧲 Scientists find new quantum behavior in unusual superconducting material

https://phys.org/news/2025-08-scientists-quantum-behavior-unusual-superconducting.html

#condmat #physics #superconductors #magnetism #solidstate

🧊 Boil, freeze, bubble, crack, repeat! Scientists simulate the solar system's 'ice volcanoes' in the lab

https://phys.org/news/2025-07-scientists-simulate-solar-ice-volcanoes.html

#space #ice #condmat #astronomy #solarsystem #planetary #experiment

We just submitted the first QUINTO draft of paper to a journal. Let's see what the editors and reviewers think.

The paper is about fractional quantum Hall states in atomic arrays. Here is the popular summary we submitted alongside:

"When atoms are arranged in a regular, dense array, their response to light can change drastically. The photons can bounce between the atoms, getting absorbed and re-emitted again and interfering with themselves. This field of quantum optics with atomic arrays is of active interest. Due to interactions, the limit of many absorbed photons generally remains hard to model, but at the same time may result in new, counterintuitive physical phenomena. In the search for ways to understand such systems, we can look for analogies in condensed matter physics, where the behavior of many interacting particles (electrons in this case) has been studied for decades. Here, we report on finding such an analogy between the behavior of few photons absorbed by an array and peculiar many-electron quantum states known as fractional quantum Hall (FQH) states. FQH states display many counterintuitive properties -- for example the electrons behave like they decomposed into pieces (e.g. "one third of an electron"), even though we know that in reality they are indivisible. Now we know that photons in arrays can behave similarly."

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#physics #science #CondensedMatterPhysics #CondensedMatter #condMat #QuantumOptics #Quantum @physics

We just came back from the "Light-Matter Interactions and Collective Effects" workshop in Paris. We heard some interesting talks on how quantum emitters (not only atoms, but also e.g. molecules and quantum dots) interact with each other and how people try to arrange them into arrays (like, putting chains of molecules inside a carbon nanotube). Darrick (my boss and supervisor of the project) gave a talk on spin liquids, while I presented a poster on fractional quantum Hall states in atom arrays.

#physics #quantum #science #QuantumOptics #CondensedMatter #CondMat

💔 A new law gives the energy needed to fracture stretchable networks

https://phys.org/news/2025-03-law-energy-fracture-stretchable-networks.html

#physics #fracture #condmat #networks

Fractional quantum Hall states in atom arrays

Our second approach to create a topological order in atom arrays is to focus on a different kind of topological order: fractional quantum Hall (FQH) states. These were first discovered in condensed matter. It is possible to confine electrons to move in two-dimensions only (such as in the 2D material graphene or in so-called metal-oxide-semiconductor transistors) and then put them in a strong perpendicular magnetic fields. The electrons then move in circles (so-called “cyclotron motion”), but since they are quantum objects, only some values of radius are allowed. Thus, the energy can only take certain fixed values (we call them “Landau levels”). There are however different possibilities of an electron having the same energy, because the center of the orbit can be located in different places – we say that Landau levels are “degenerate”. And when there is degeneracy, the interaction between electrons becomes very important. Without interactions, there are many possible ways of arranging electrons within a Landau level, all with the same energy. In the presence of interactions, some arrangements become preferred – and it turns out those correspond to topological orders known as the FQH states. Such systems host anyons which look like fractions of an electron – like somehow the electron split into several parts.

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#Physics #science #TopologicalOrder #Quantum #QuantumOptics #CondensedMatter #CondMat #cond_mat #QuantumHall

Spin liquids in Rydberg atom arrays in cavities

What is our proposal for the realization of spin liquid?

We consider an atom array held by optical tweezers and placed in an optical cavity. The cavity consists of two mirrors placed on the opposite sides of the system. The photons which normally would escape the system (at least some of them) will bounce back and forth between the mirrors. In such a configuration, the distance between atoms becomes irrelevant and the probability of an excitation hopping between any two atoms becomes the same.

The second ingredient is that the excited state of the atoms would be a Rydberg state – a very high-energy state where the electron is far away from the nucleus. The atoms in Rydberg states interact strongly by van der Waals forces. In our case it would mean that two excitations will have much higher energy when they are at nearest-neighboring atoms than if they are far away.

This setting seems much different from usual crystals. In the typical material, the electrons are much more likely to hop between nearest-neighboring atoms than far-away ones, while in our case they would be able hop arbitrarily far with the same probability. But it turns out that there is in equivalence between such “infinite-range hopping + Rydberg” model and the Heisenberg model, commonly used to describe magnets, including the frustrated ones.
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#Physics #Quantum #TopologicalOrder #CondMat #CondensedMatter #QuantumOptics #Science

Atom arrays

Scientists have developed ways of trapping atoms and arranging them in space using laser beams (such as “optical tweezers” and “optical lattices”). What can one do using these tools? One possibility is arranging the atoms in a regular array.

Why people find it interesting? It was found that such systems have properties much different than clouds of atoms randomly flying around. The lattice structure changes how the atoms emit and absorb light. This is because light emitted from different atoms can interfere, and a regular structure of array works like a diffraction grating. This happens especially if the distance between atoms is smaller than one wavelength.

For example, a 1D chain of atoms in a certain state emits light only on its ends. And a 2D array can act as a perfect mirror (for certain wavelength), even though it is only one atom thin.

It was theoretically shown that these effects can be used to boost the efficiency of optical quantum devices such as memories and gates, which may be used in the future for a “quantum internet” and quantum computers.

#Physics #Science #Quantum #QuantumOptics #atoms #CondensedMatter #CondMat

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💔 New general law governs fracture energy of networks across materials and length scales

https://techxplore.com/news/2025-01-general-law-fracture-energy-networks.html

#fracture #physics #scaling #condmat #materials