Superradiant Phase Transition of Fermi Gases in a Cavity across a Feshbach Resonance

Abstract

In this letter we consider the superradiant phase transition of a two-component Fermi gas in a cavity across a Feshbach resonance. It is known that quantum statistics plays a crucial role for the superradiant phase transition in atomic gases; in contrast to bosons, in a Fermi gas this transition exhibits strong density dependence. We show that across a Feshbach resonance, while the two-component Fermi gas passes through the BEC-BCS crossover, the superradiant phase transition undergoes a corresponding crossover from a fermionic behavior on the weakly interacting BCS side, to a bosonic behavior on the molecular BEC side. This intricate statistics crossover makes the superradiance maximally enhanced either in the unitary regime for low densities, in the BCS regime for moderate densities close to Fermi surface nesting, or in the BEC regime for high densities.

References in corpus (6)

• Theory of ultracold Fermi gases
• Strong atom-field coupling for Bose-Einstein condensates in an optical cavity on a chip
• Cavity QED with a Bose-Einstein condensate
• Roton-type mode softening in a quantum gas with cavity-mediated long-range interactions
• Quantum charge glasses of itinerant fermions with cavity-mediated long-range interactions
• Cold Fermi atomic gases in a pumped optical resonator

Cited by in corpus (10)

• Cavity QED with Quantum Gases: New Paradigms in Many-Body Physics
• Density-wave ordering in a unitary Fermi gas with photon-mediated interactions
• Strongly correlated Fermions strongly coupled to light
• Cavity-assisted preparation and detection of a unitary Fermi gas
• Non-equilibrium phases of Fermi gas inside a cavity with imbalanced pumping
• Fluctuation-Induced Bistability of Fermionic Atoms Coupled to a Dissipative Cavity
• Superradiant phase transitions in one-dimensional correlated Fermi gases with cavity-induced umklapp scattering
• Phase transition, phase separation and mode softening of a two-component Bose-Einstein condensate in an optical cavity
• The Single Particle Excitation Spectrum of Degenerate Fermi gases in a ring cavity
• Tuning Density and Spin Ordering of Degenerate Fermi Gases in an Optical Cavity