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arXiv · 2403.08602

Exploring global symmetry-breaking superradiant phase via phase competition

Hai-Chao Li·Wen Huang·Wei Xiong
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Abstract

Superradiant phase transitions play a fundamental role in understanding the mechanism of collective light-matter interaction at the quantum level. Here we investigate multiple superradiant phases and phase transitions with different symmetry-breaking patterns in a two-mode V-type Dicke model. Interestingly, we show that there exists a quadruple point where one normal phase, one global symmetry-breaking superradiant phase and two local symmetry-breaking superradiant phases meet. Such a global phase results from the phase competition between two local superradiant phases and can not occur in the standard $\Lambda$- and $\Xi$-type three-level configurations in quantum optics. Moreover, we exhibit a sequential first-order quantum phase transition from one local to the global again to the other local superradiant phase. Our study opens up a perspective of exploring multi-level quantum critical phenomena with global symmetry breaking.

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Hai-Chao Li, Wen Huang, Wei Xiong. 2024-03-13. Exploring global symmetry-breaking superradiant phase via phase competition. https://doi.org/10.1364/ol.522886

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