Quantum spin liquids bootstrapped from Ising criticality in Rydberg arrays

Journal Article · Wed Sep 14 00:00:00 EDT 2022 · Physical Review. B

DOI:https://doi.org/10.1103/physrevb.106.115122· OSTI ID:1982786

Slagle, Kevin ^[1]; Liu, Yue ^[2]; Aasen, David ^[3]; Pichler, Hannes ^[4]; Mong, Roger K. ^[5]; Chen, Xie ^[2]; Endres, Manuel ^[2]; Alicea, Jason ^[2]

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1. Rice Univ., Houston, TX (United States); California Institute of Technology (CalTech), Pasadena, CA (United States)
2. California Institute of Technology (CalTech), Pasadena, CA (United States)
3. Univ. of California, Santa Barbara, CA (United States)
4. California Institute of Technology (CalTech), Pasadena, CA (United States); Univ. Innsbruck (Austria); Austrian Academy of Sciences, Innsbruck (Austria)
5. Univ. of Pittsburgh, PA (United States)

Arrays of Rydberg atoms constitute a highly tunable, strongly interacting venue for the pursuit of exotic states of matter. We develop a strategy for accessing a family of fractionalized phases known as quantum spin liquids in two-dimensional Rydberg arrays. We specifically use effective field theory methods to study arrays assembled from Rydberg chains tuned to an Ising phase transition that famously hosts emergent fermions propagating within each chain. This highly entangled starting point allows us to naturally access spin liquids familiar from Kitaev's honeycomb model—albeit from an entirely different framework. In particular, we argue that finite-range repulsive Rydberg interactions, which frustrate nearby symmetry-breaking orders, can enable coherent propagation of emergent fermions between the chains in which they were born. Delocalization of emergent fermions across the full two-dimensional Rydberg array yields a gapless Z₂ spin liquid with a single massless Dirac cone. Here, the Rydberg occupation numbers exhibit universal power-law correlations that provide a straightforward experimental diagnostic of this phase. We further show that explicitly breaking symmetries perturbs the gapless spin liquid into gapped, topologically ordered descendants: Breaking lattice symmetries generates toric-code topological order, whereas introducing Floquet-mediated chirality generates non-Abelian Ising topological order. In the toric-code phase, we analytically construct microscopic incarnations of non-Abelian defects, which can be created and transported by dynamically controlling the atom positions in the array. Our work suggests that appropriately tuned Rydberg arrays provide a cold-atoms counterpart of solid-state “Kitaev materials” and, more generally, it spotlights a different angle for pursuing experimental platforms for Abelian and non-Abelian fractionalization.

• Research Organization: National Quantum Information Science (QIS) Research Centers (United States). The Quantum Science Center (QSC)
• Sponsoring Organization: Defense Advanced Research Projects Agency (DARPA); Gordon and Betty Moore Foundation; National Science Foundation (NSF); US Air Force Office of Scientific Research (AFOSR); US Army Research Office (ARO); USDOE Office of Science (SC)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1982786
• Journal Information: Physical Review. B, Journal Name: Physical Review. B Journal Issue: 11 Vol. 106; ISSN 2469-9950
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Kitaev model
Physics
Rydberg atoms & molecules
anyons
bosonization
topological defects
topological phases of matter