Fractional Quantum Hall States of Rydberg Polaritons

TL;DR

This paper proposes a method to realize fractional quantum Hall states of light using Rydberg polaritons in an optical cavity array, leveraging dipolar interactions to create topological flat bands and fractional Chern insulators.

Contribution

It introduces a novel scheme to generate fractional quantum Hall states of light through Rydberg polaritons and topological flat bands in an optical cavity array.

Findings

Demonstrates how dipolar interactions create topological flat bands for polaritons.

Shows the possibility of realizing fractional Chern insulators with light.

Proposes a feasible experimental setup for photonic fractional quantum Hall states.

Abstract

We propose a scheme for realizing fractional quantum Hall states of light. In our scheme, photons of two polarizations are coupled to different atomic Rydberg states to form two flavors of Rydberg polaritons that behave as an effective spin. An array of optical cavity modes overlapping with the atomic cloud enables the realization of an effective spin-1/2 lattice. We show that the dipolar interaction between such polaritons, inherited from the Rydberg states, can be exploited to create a flat, topological band for a single spin-flip excitation. At half filling, this gives rise to a photonic (or polaritonic) fractional Chern insulator -- a lattice-based, fractional quantum Hall state of light.