arXiv:hep-ph/0312275 · Physical Review A

Cold asymmetrical fermion superfluids

Heron Caldas

Published Jun 4, 2004• 111 citations

Abstract

In this work we investigate the general properties and the ground state of an asymmetrical dilute gas of cold fermionic atoms, formed by two particle species having different densities. We have shown in a recent paper, that a mixed phase composed of normal and superfluid components is the energetically favored ground state of such a cold fermionic system. Here we extend the analysis and verify that in fact, the mixed phase is the preferred ground state of an asymmetrical superfluid in various situations. We predict that the mixed phase can serve as a way of detecting superfluidity and estimating the magnitude of the gap parameter in asymmetrical fermionic systems.

DOI: 10.1103/physreva.69.063602

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