Optomechanics of a Quantum-Degenerate Fermi Gas

TL;DR

This paper theoretically investigates the optomechanical interaction between light and a collective density oscillation mode in ultracold fermionic atoms within a cavity, revealing analogies to bosonic condensates and potential experimental effects.

Contribution

It derives an effective Hamiltonian for fermionic atom optomechanics, highlighting the analogy to bosonic systems and exploring experimental implications.

Findings

Effective Hamiltonian similar to standard optomechanical systems

Predicted optical bistability due to fermionic density oscillations

Analyzed noise spectrum modifications from optomechanical coupling

Abstract

We explore theoretically the optomechanical interaction between a light field and a mechanical mode of ultracold fermionic atoms inside a Fabry-P\'{e}rot cavity. The low-lying phonon mode of the fermionic ensemble is a collective density oscillation associated with particle-hole excitations, and is mathematically analogous to the momentum side-mode excitations of a bosonic condensate. The mechanical motion of the fermionic particle-hole system behaves hence as a ``moving mirror.'' We derive an effective system Hamiltonian that has the form of generic optomechanical systems. We also discuss the experimental consequences the optomechanical coupling in optical bistability and in the noise spectrum of the system.