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

Laughlin-like states of few atomic excitations in small subwavelength atom arrays

Atom arrays with sub-wavelength lattice constant can exhibit fascinating optical properties. Up to now, much of our understanding of these systems focuses on the single-excitation regime. In one relevant example, the combination of multiple excited states and magnetic fields can yield topological band structures, albeit with dispersion relations that can exhibit divergences near the light cone. Here, we go beyond the single-excitation level to show that such systems can give rise to few-particle Laughlin-like states. In particular, we consider small honeycomb ``flakes,'' where the divergences can be smeared out by finite-size effects. By choosing an appropriate value of magnetic field we thereby obtain an energy spectrum and eigenstates resembling those of Landau levels. The native hard-core nature of atomic excitations then gives rise to multi-excitation Laughlin-like states. This phenomenon occurs not only in samples of tens of sites, but also in a minimal nanoring system of only six sites. Next, considering two-particle Laughlin-like states, we show that they can be driven by uniform light, and that correlations of the output light contain identifying fingerprints of these states. We believe that these results are a step towards new paradigms of engineering and understanding strongly-correlated many-body states in atom-light interfaces.

arXiv.org