Self-trapping of a Fermi super-fluid in a double-well potential in the BEC-unitarity crossover

TL;DR

This paper develops a generalized density-functional equation to study the self-trapping behavior of a Fermi super-fluid across the BEC-unitarity crossover in a double-well potential, providing both numerical and analytical insights.

Contribution

It introduces a new generalized equation for Fermi super-fluids in the BEC-unitarity crossover and analyzes self-trapping phenomena with a combined numerical and analytical approach.

Findings

Self-trapping occurs across the BEC-unitarity crossover.

A simple two-mode model captures the essential physics.

Results have implications for atomic BEC in double-well traps.

Abstract

We derive a generalized Gross-Pitaevskii density-functional equation appropriate to study the Bose-Einstein condensate (BEC) of dimers formed of singlet spin-half Fermi pairs in the BEC-unitarity crossover while the dimer-dimer scattering length $a$ changes from 0 to $\infty$. Using an effective one-dimensional form of this equation, we study the phenomenon of dynamical self-trapping of a cigar-shaped Fermi super-fluid in the entire BEC-unitarity crossover in a double-well potential. A simple two-mode model is constructed to provide analytical insights. We also discuss the consequence of our study on the self-trapping of an atomic BEC in a double-well potential.