Dissipative phase transition with driving-controlled spatial dimension and diffusive boundary conditions

TL;DR

This paper explores how a first-order dissipative phase transition in a polariton system depends on the spatial dimension and boundary conditions, demonstrating a transition in 2D but not in 1D through theory and experiments.

Contribution

It introduces a method to tune the system's spatial dimension via optical driving profiles and shows the emergence of a phase transition in 2D but not in 1D.

Findings

No phase transition in 1D driving geometry.

First-order phase transition observed in 2D system.

Experimental and theoretical results are consistent.

Abstract

We investigate theoretically and experimentally a first-order dissipative phase transition, with diffusive boundary conditions and the ability to tune the spatial dimension of the system. The considered physical system is a planar semiconductor microcavity in the strong light-matter coupling regime, where polariton excitations are injected by a quasi-resonant optical driving field. The spatial dimension of the system from 1D to 2D is tuned by designing the intensity profile of the driving field. We investigate the emergence of criticality by increasing the spatial size of the driven region. The system is nonlinear due to polariton-polariton interactions and the boundary conditions are diffusive because the polaritons can freely diffuse out of the driven region. We show that no phase transition occurs using a 1D driving geometry, while for a 2D geometry we do observe both in theory and experiments the emergence of a first-order phase transition.