On multicomponent polariton superfluidity in the optical parametric oscillator regime

TL;DR

This paper investigates superfluidity in driven-dissipative polariton systems within the optical parametric oscillator regime, revealing complex behaviors of multiple coupled fluids and their responses to defects, combining theoretical and experimental insights.

Contribution

It provides the first detailed analysis of multicomponent superfluidity in polariton OPOs, highlighting the distinct responses of pump, signal, and idler fluids to static defects.

Findings

Signal fluid exhibits minimal modulations when encountering defects.

Pump and idler fluids show modulations influenced by nonlinear and parametric coupling.

Macroscopic coherence leads to quantized flow metastability in signal and idler.

Abstract

Superfluidity, the ability of a liquid or gas to flow with zero viscosity, is one of the most remarkable implications of collective quantum coherence. In equilibrium systems like liquid 4He and ultracold atomic gases, superfluid behaviour conjugates diverse yet related phenomena, such as persistency of metastable flow in multiply connected geometries and the existence of a critical velocity for frictionless flow when hitting a static defect. The link between these different aspects of superfluid behaviour is far less clear in driven-dissipative systems displaying collective coherence, such as microcavity polaritons, which raises important questions about their concurrency. With a joint theoretical and experimental study, we show that the scenario is particularly rich for polaritons driven in a three-fluid collective coherent regime so-called optical parametric oscillator. On the one hand, the spontaneous macroscopic coherence following the phase locking of the signal and idler fluids has been shown to be responsible for their simultaneous quantized flow metastability. On the other hand, we show here that pump, signal and idler have distinct responses when hitting a static defect; while the signal displays hardly appreciable modulations, the ones appearing in pump and idler are determined by their mutual coupling due to nonlinear and parametric processes.