Fermionic Superradiance in a Transversely Pumped Optical Cavity

TL;DR

This paper explores how ultra cold spinless fermions in a transversely pumped optical cavity exhibit a zero-temperature superradiant phase transition, revealing unique effects due to Pauli blocking and lattice commensuration.

Contribution

It provides the first theoretical analysis of fermionic superradiance in a cavity, highlighting differences from bosonic systems and predicting novel phase transition behaviors.

Findings

Identifies a zero-temperature superradiant phase transition for fermions.

Discovers lattice commensuration effects due to Pauli blocking.

Predicts discontinuous transitions and tricritical points in the phase diagram.

Abstract

Following the experimental realization of Dicke superradiance in Bose gases coupled to cavity light fields, we investigate the behavior of ultra cold fermions in a transversely pumped cavity. We focus on the equilibrium phase diagram of spinless fermions coupled to a single cavity mode and establish a zero temperature transition to a superradiant state. In contrast to the bosonic case, Pauli blocking leads to lattice commensuration effects that influence self-organization in the cavity light field. This includes a sequence of discontinuous transitions with increasing atomic density and tricritical superradiance. We discuss the implications for experiment.