Dynamical phase transition of light in time-varying nonlinear dispersive media

TL;DR

This paper uncovers a prethermal dynamical phase transition in fluctuating optical beams within nonlinear dispersive media, triggered by sudden changes in medium parameters, revealing critical behavior and scaling properties akin to quantum field models.

Contribution

It introduces the concept of a temporal interface inducing a dynamical phase transition in optical beams, linking optical phenomena to quantum field theory models.

Findings

Correlation length diverges algebraically at the transition

Below critical quench, the beam shows algebraic relaxation and self-similarity

Identifies a dimensional cross-over of the critical exponent

Abstract

We demonstrate the existence of a prethermal dynamical phase transition (DPT) for fluctuating optical beams propagating in nonlinear dispersive media. The DPT can be probed by suddenly changing in time the dispersion and nonlinearity parameters of the medium (thus realizing a "temporal interface"), a procedure that emulates a quench in a massive $\varphi^4$ model. Above a critical value of the quench identifying the transition, the fluctuating beam after the temporal interface is characterized by a correlation length that diverges algebraically at the transition. Below the critical quench, the beam exhibits an algebraic relaxation and a self-similar scaling. Our analysis also reveals a dimensional cross-over of the critical exponent, a characteristic feature of the optical DPT.