Photonics
Tunable Multicriticality in a Dissipative Superradiant Phase Transition via Optical Squeezing
Yuanyi Huang, Gui‐Lei Zhu, Lin Cheng, Xiaoguang Wang
Abstract
Dissipation can fundamentally reconstruct the multicritical structure of driven-dissipative light–matter systems. In the interpolating Dicke–Tavis–Cummings model, cavity loss eliminates the U(1)-symmetric superradiant phase on the Tavis–Cummings line λx=λy and splits the original multicritical point into a pair of dissipation-induced tricritical points. Here, we show that intracavity optical squeezing provides a coherent means of continuously reshaping this loss-generated multicritical structure. The single-mode parametric interaction acts asymmetrically on the two cavity quadratures, thereby deforming the phase boundaries and continuously tuning the dissipation-induced tricritical points. We analytically determine the phase boundaries and the evolution of the tricritical structure with the parametric gain and cavity dissipation, and show that the two tricritical points coalesce in the weak-loss limit. Photon-number fluctuations provide clear quantum signatures of the squeezing-controlled multicritical structure.