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Title: Polarized fermions in the unitarity limit

Abstract

We consider a polarized Fermi gas in the unitarity limit. Results are calculated analytically up to next-to-leading order in an expansion about d=4 spatial dimensions. We find a first order transition from superfluid to normal phase. The critical chemical potential asymmetry for this phase transition is {delta}{mu}{sub c}=(2{mu}/{epsilon})(1-0.467{epsilon}), where {epsilon}=4-d is the expansion parameter and {mu} is the average chemical potential of the two fermion species. Stability of the superfluid phase in the presence of supercurrents is also studied.

Authors:
; ;  [1];  [2]
  1. Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20982157
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.023606; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASYMMETRY; BOSE-EINSTEIN CONDENSATION; COMPUTER CALCULATIONS; EXPANSION; FERMI GAS; FERMIONS; PHASE TRANSFORMATIONS; POLARIZATION; POTENTIALS; STABILITY; SUPERFLUIDITY; UNITARITY

Citation Formats

Rupak, Gautam, Schaefer, Thomas, Kryjevski, Andrei, and Nuclear Theory Center, Indiana University, Bloomington, Indiana 47408. Polarized fermions in the unitarity limit. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.023606.
Rupak, Gautam, Schaefer, Thomas, Kryjevski, Andrei, & Nuclear Theory Center, Indiana University, Bloomington, Indiana 47408. Polarized fermions in the unitarity limit. United States. doi:10.1103/PHYSREVA.75.023606.
Rupak, Gautam, Schaefer, Thomas, Kryjevski, Andrei, and Nuclear Theory Center, Indiana University, Bloomington, Indiana 47408. Thu . "Polarized fermions in the unitarity limit". United States. doi:10.1103/PHYSREVA.75.023606.
@article{osti_20982157,
title = {Polarized fermions in the unitarity limit},
author = {Rupak, Gautam and Schaefer, Thomas and Kryjevski, Andrei and Nuclear Theory Center, Indiana University, Bloomington, Indiana 47408},
abstractNote = {We consider a polarized Fermi gas in the unitarity limit. Results are calculated analytically up to next-to-leading order in an expansion about d=4 spatial dimensions. We find a first order transition from superfluid to normal phase. The critical chemical potential asymmetry for this phase transition is {delta}{mu}{sub c}=(2{mu}/{epsilon})(1-0.467{epsilon}), where {epsilon}=4-d is the expansion parameter and {mu} is the average chemical potential of the two fermion species. Stability of the superfluid phase in the presence of supercurrents is also studied.},
doi = {10.1103/PHYSREVA.75.023606},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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  • The unitarity regime of the BCS-BEC crossover can be realized by diluting a system of two-component lattice fermions with an on-site attractive interaction. We perform a systematic-error-free finite-temperature simulation of this system by diagrammatic determinant Monte Carlo method. The critical temperature in units of Fermi energy is found to be T{sub c}/{epsilon}{sub F}=0.152(7). We also report the behavior of the thermodynamic functions, and discuss the issues of thermometry of ultracold Fermi gases.
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