Searching for the Kardar-Parisi-Zhang phase in microcavity polaritons

TL;DR

This paper demonstrates through numerical simulations that microcavity polaritons in the optical parametric oscillator regime can exhibit Kardar-Parisi-Zhang physics in 2D, supporting future experimental observation.

Contribution

It provides the first numerical validation that KPZ universality can be realized in microcavity polaritons under specific pumping conditions, confirming analytical predictions.

Findings

KPZ phase is robust against vortices and effects.

Spatial correlations match KPZ universality.

Phase fluctuations follow KPZ distribution.

Abstract

Recent approximate analytical work has suggested that, at certain values of the external pump, the optical parametric oscillator (OPO) regime of microcavity polaritons may provide a long sought realisation of Kardar-Parisi-Zhang (KPZ) physics in 2D. Here, by solving the full microscopic model numerically using the truncated Wigner method, we prove that this predicted KPZ phase for OPO is robust against the appearance of vortices or other effects. For those pump strengths, spatial correlations in the direction perpendicular to the pump, and the distribution of phase fluctuations, match closely to the forms characteristic of the KPZ universality. This strongly indicates the viability of observing KPZ behaviour in future polariton OPO experiments.