Boson-like quantum dynamics of association in ultracold Fermi gases

TL;DR

This paper demonstrates that the collective association dynamics of ultracold Fermi gases exhibit boson-like behavior, with enhanced rates due to many-particle interference, and introduces a simplified model for large systems.

Contribution

It presents a reduced dynamical system for fermionic association, enabling realistic calculations and revealing boson-like collective effects in ultracold Fermi gases.

Findings

Association rates are enhanced with the number of holes.

Dissociation rates increase with the number of particles.

The dynamics resemble bosonic systems under a fermion-hole mapping.

Abstract

We study the collective association dynamics of a cold Fermi gas of $2N$ atoms in $M$ atomic modes into a single molecular bosonic mode. The many-body fermionic problem for $2^M$ amplitudes is effectively reduced to a dynamical system of $\min\{N,M\}+1$ amplitudes, making the solution no more complex than the solution of a two-mode Bose-Einstein condensate and allowing realistic calculations with up to $10^4$ particles. The many-body dynamics is shown to be formally similar to the dynamics of the bosonic system under the mapping of boson particles to fermion holes, producing collective enhancement effects due to many-particle constructive interference. Dissociation rates are shown to enhance as the number of particles whereas association rates are enhanced as the number of holes, leading to boson-like collective behavior.