Quantum critical regime in a quadratically-driven nonlinear photonic lattice

TL;DR

This paper investigates a quadratically-driven nonlinear photonic lattice, revealing a quantum critical point akin to the quantum Ising model, and explores the transition to a quantum critical regime influenced by dissipation.

Contribution

It introduces a detailed analysis of the quantum critical behavior in a driven-dissipative photonic lattice using finite-size scaling and corner-space renormalization.

Findings

Identification of a quantum Ising universality class critical point.

Observation of a transition from universal quantum behavior to a quantum critical regime.

Demonstration of the impact of photon loss rates on critical phenomena.

Abstract

We study an array of coupled optical cavities in presence of two-photon driving and dissipation. The system displays a critical behavior similar to that of a quantum Ising model at finite temperature. Using the corner-space renormalization method, we compute the steady-state properties of finite lattices of varying size, both in one- and two-dimensions. From a finite-size scaling of the average of the photon number parity, we highlight the emergence of a critical point in regimes of small dissipations, belonging to the quantum Ising universality class. For increasing photon loss rates, a departure from this universal behavior signals the onset of a quantum critical regime, where classical fluctuations induced by losses compete with long-range quantum correlations.