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arXiv · 2603.13657

Superradiant strongly correlated quantum states in cavity Hubbard model

Kang Wang·Wei-Xuan Chang·Cheng-Yu Bi·Zi Cai·Zi-Xiang Li
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Abstract

In cavity quantum materials, entangling strongly correlated electrons with quantum light provides a unique opportunity to explore novel quantum phases and phase transitions absent in conventional solid-state materials. In this study, we develop a sign-problem-free fermion-photon hybrid Quantum Monte Carlo (QMC) algorithm, and use it to systematically investigate the ground-state phase diagram of a two-dimensional cavity Hubbard model. It is shown that the interplay between the electron correlation and photon condensation gives rise to intriguing quantum phases ({\it e.g.} superradiant antiferromagnetic and chiral/$\pi$-flux states), and different quantum phase transitions, such as a first-order superradiant phase transition and a continuous phase transition with Gross-Neveu universality class. The methodology can be readily generalized to more complicated cavity strongly correlated models.

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Kang Wang, Wei-Xuan Chang, Cheng-Yu Bi, Zi Cai, Zi-Xiang Li. 2026-03-13. Superradiant strongly correlated quantum states in cavity Hubbard model. https://arxiv.org/abs/2603.13657

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