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Title: Superfluidity in three-species mixtures of Fermi gases across Feshbach resonances

Abstract

In this Rapid Communication a generalization of the BEC-BCS crossover theory to a multicomponent superfluid is presented by studying a three-species mixture of Fermi gas across two Feshbach resonances. At the BEC side of resonances, two kinds of molecules are stable which gives rise to a two-component Bose condensate. This two-component superfluid state can be experimentally identified from the radio-frequency spectroscopy, density profile, and short noise measurements. As approaching the BCS side of resonances, the superfluidity will break down at some point and yield a first-order quantum phase transition to normal state, due to the mismatch of three Fermi surfaces. Phase separation instability will occur around the critical regime.

Authors:
 [1]
  1. Department of Physics, Ohio-State University, Columbus, Ohio 43210 (United States)
Publication Date:
OSTI Identifier:
20982225
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.031603; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; BCS THEORY; BOSE-EINSTEIN CONDENSATION; COMMUNICATIONS; CONDENSATES; DENSITY; FERMI GAS; FERMI LEVEL; FERMIONS; INSTABILITY; MIXTURES; MOLECULES; NOISE; PHASE TRANSFORMATIONS; RADIOWAVE RADIATION; RESONANCE; SPECTROSCOPY; SUPERFLUIDITY

Citation Formats

Zhai, Hui. Superfluidity in three-species mixtures of Fermi gases across Feshbach resonances. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.031603.
Zhai, Hui. Superfluidity in three-species mixtures of Fermi gases across Feshbach resonances. United States. doi:10.1103/PHYSREVA.75.031603.
Zhai, Hui. Thu . "Superfluidity in three-species mixtures of Fermi gases across Feshbach resonances". United States. doi:10.1103/PHYSREVA.75.031603.
@article{osti_20982225,
title = {Superfluidity in three-species mixtures of Fermi gases across Feshbach resonances},
author = {Zhai, Hui},
abstractNote = {In this Rapid Communication a generalization of the BEC-BCS crossover theory to a multicomponent superfluid is presented by studying a three-species mixture of Fermi gas across two Feshbach resonances. At the BEC side of resonances, two kinds of molecules are stable which gives rise to a two-component Bose condensate. This two-component superfluid state can be experimentally identified from the radio-frequency spectroscopy, density profile, and short noise measurements. As approaching the BCS side of resonances, the superfluidity will break down at some point and yield a first-order quantum phase transition to normal state, due to the mismatch of three Fermi surfaces. Phase separation instability will occur around the critical regime.},
doi = {10.1103/PHYSREVA.75.031603},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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