arXiv subjects

M. Soriente

Publications and source records attributed to M. Soriente.

2 recordsLinked to original sources

arXiv2021

Noise-Resilient Phase Transitions and Limit-Cycles in Coupled Kerr Oscillators

Driven-dissipative quantum many-body systems have been the subject of many studies in recent years. They possess unique, novel classes of dissipation-stabilized quantum many-body phases including the limit cycle. For a long time it has been speculated if such a behavior, a recurring phenomenon in non-linear classical and quantum many-body systems, can be classified as a time crystal. However, the robustness of these periodic dynamics, against quantum fluctuations is an open question. In this work we seek the answer to this question in a canonical yet important system, i.e., a multi-mode cavity with self and cross-Kerr non-linearity, including the fluctuation effects via higher order correlations. Employing the Keldysh path integral, we investigate the Green's function and correlation of the cavity modes in different regions. Furthermore, we extend our analysis beyond the mean-field by explicitly including the effect of two-body correlations via the 2nd-cumulant expansion. Our results shed light on the emergence of dissipative phase transitions in open quantum systems and clearly indicate the robustness of limit-cycle oscillations in the presence of the quantum fluctuations.

quant-ph↗

arXiv2019

Distinguishing phases using the dynamical response of driven-dissipative light-matter systems

We present a peculiar transition triggered by infinitesimal dissipation in the interpolating Dicke-Tavis-Cummings model. The model describes a ubiquitous light-matter setting using a collection of two-level systems interacting with quantum light trapped in an optical cavity. In a previous work [Phys. Rev. Lett. 120, 183603 (2018)], dissipation was shown to extend a normal phase (dark state) into new regions of the model's parameter space. Harnessing Keldysh's action formalism to compute the response function of the light, we show that the normal phase does not merely spread but encompasses a transition between the old and the dissipation-stabilized regimes of the normal phase. This transition, however, solely manifests in the dynamical fluctuations atop the empty cavity, through stabilization of an excited state of the closed system. Consequently, we reveal that the fluctuations flip from being particlelike to holelike across this transition. This inversion is also accompanied by the behavior of the Liouvillian eigenvalues akin to exceptional points. Our work forges the way to discovering transitions in a wide variety of driven-dissipative systems and is highly pertinent for current experiments.

cond-mat.quant-gas↗