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Title: Temperature of a trapped unitary Fermi gas at finite entropy

Abstract

We present theoretical predictions for the equation of state of a harmonically trapped Fermi gas in the unitary limit. Our calculations compare Monte Carlo results with the equation of state of a uniform gas using three distinct perturbation schemes. We show that in experiments the temperature can be usefully calibrated by making use of the entropy, which is invariant during an adiabatic conversion into the weakly interacting limit of molecular BEC. We predict the entropy dependence of the equation of state.

Authors:
; ;  [1]
  1. ARC Centre of Excellence for Quantum-Atom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072 (Australia)
Publication Date:
OSTI Identifier:
20974632
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.023617; (c) 2006 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; BOSE-EINSTEIN CONDENSATION; DISTURBANCES; ENTROPY; EQUATIONS OF STATE; FERMI GAS; FERMIONS; MONTE CARLO METHOD; PERTURBATION THEORY; TRAPPING

Citation Formats

Hu Hui, Liu Xiaji, and Drummond, Peter D. Temperature of a trapped unitary Fermi gas at finite entropy. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.023617.
Hu Hui, Liu Xiaji, & Drummond, Peter D. Temperature of a trapped unitary Fermi gas at finite entropy. United States. doi:10.1103/PHYSREVA.73.023617.
Hu Hui, Liu Xiaji, and Drummond, Peter D. Wed . "Temperature of a trapped unitary Fermi gas at finite entropy". United States. doi:10.1103/PHYSREVA.73.023617.
@article{osti_20974632,
title = {Temperature of a trapped unitary Fermi gas at finite entropy},
author = {Hu Hui and Liu Xiaji and Drummond, Peter D.},
abstractNote = {We present theoretical predictions for the equation of state of a harmonically trapped Fermi gas in the unitary limit. Our calculations compare Monte Carlo results with the equation of state of a uniform gas using three distinct perturbation schemes. We show that in experiments the temperature can be usefully calibrated by making use of the entropy, which is invariant during an adiabatic conversion into the weakly interacting limit of molecular BEC. We predict the entropy dependence of the equation of state.},
doi = {10.1103/PHYSREVA.73.023617},
journal = {Physical Review. A},
number = 2,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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  • We investigate the dynamical properties of a trapped finite-temperature normal Fermi gas with dipole-dipole interaction. For the free-expansion dynamics, we show that the expanded gas always becomes stretched along the direction of the dipole moment. In addition, we present the temperature and interaction dependences of the asymptotic aspect ratio. We further study the collapse dynamics of the system by suddenly increasing the dipolar interaction strength. We show that, in contrast to the anisotropic collapse of a dipolar Bose-Einstein condensate, a dipolar Fermi gas always collapses isotropically when the system becomes globally unstable. We also explore the interaction and temperature dependencesmore » for the frequencies of the low-lying collective excitations.« less