Generation and spectroscopic signatures of a fractional quantum Hall liquid of photons in an incoherently pumped optical cavity

TL;DR

This paper proposes a method to create and detect a fractional quantum Hall state of photons in an optical cavity using incoherent pumping and spectroscopy, advancing quantum simulation of topological states.

Contribution

It introduces a driven-dissipative model for strongly interacting photons to realize and identify a bosonic Laughlin state in an optical cavity.

Findings

Feasibility of generating a Laughlin state of light with incoherent pumping.

Use of angular momentum-selective spectroscopy to identify quantum Hall states.

Demonstration of controlling fluctuations and edge modes via external potentials.

Abstract

We theoretically investigate a driven-dissipative model of strongly interacting photons in a nonlinear optical cavity in the presence of a synthetic magnetic field. We show the possibility of using a frequency-dependent incoherent pump to create a strongly-correlated $\nu = 1/2$ bosonic Laughlin state of light: thanks to the incompressibility of the Laughlin state, fluctuations in the total particle number and excitation of edge modes can be tamed by imposing a suitable external potential profile for photons. We further propose angular momentum-selective spectroscopy of the emitted light as a tool to obtain unambiguous signatures of the microscopic physics of the quantum Hall liquid of light.