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Title: Phase Diagram of a Strongly Interacting Polarized Fermi Gas in One Dimension

Abstract

Based on the integrable Gaudin model and local density approximation, we discuss the ground state of a one-dimensional trapped Fermi gas with imbalanced spin population, for an arbitrary attractive interaction. A phase separation state, with a polarized superfluid core immersed in an unpolarized superfluid shell, emerges below a critical spin polarization. Above it, coexistence of polarized superfluid matter and a fully polarized normal gas is favored. These two exotic states could be realized experimentally in highly elongated atomic traps, and diagnosed by measuring the lowest density compressional mode. We identify the polarized superfluid as having an Fulde-Ferrell-Larkin-Ovchinnikov structure, and predict the resulting mode frequency as a function of the spin polarization.

Authors:
 [1];  [2]; ;  [3]
  1. Department of Physics, Renmin University of China, Beijing 100872 (China)
  2. (Australia)
  3. ARC Centre of Excellence for Quantum-Atom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072 (Australia)
Publication Date:
OSTI Identifier:
20955456
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevLett.98.070403; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; FERMI GAS; GROUND STATES; INTEGRAL CALCULUS; MATTER; ONE-DIMENSIONAL CALCULATIONS; PHASE DIAGRAMS; SPIN; SPIN ORIENTATION; SUPERFLUIDITY; TRAPPING; TRAPS

Citation Formats

Hu Hui, ARC Centre of Excellence for Quantum-Atom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072, Liu Xiaji, and Drummond, Peter D. Phase Diagram of a Strongly Interacting Polarized Fermi Gas in One Dimension. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.070403.
Hu Hui, ARC Centre of Excellence for Quantum-Atom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072, Liu Xiaji, & Drummond, Peter D. Phase Diagram of a Strongly Interacting Polarized Fermi Gas in One Dimension. United States. doi:10.1103/PHYSREVLETT.98.070403.
Hu Hui, ARC Centre of Excellence for Quantum-Atom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072, Liu Xiaji, and Drummond, Peter D. Fri . "Phase Diagram of a Strongly Interacting Polarized Fermi Gas in One Dimension". United States. doi:10.1103/PHYSREVLETT.98.070403.
@article{osti_20955456,
title = {Phase Diagram of a Strongly Interacting Polarized Fermi Gas in One Dimension},
author = {Hu Hui and ARC Centre of Excellence for Quantum-Atom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072 and Liu Xiaji and Drummond, Peter D.},
abstractNote = {Based on the integrable Gaudin model and local density approximation, we discuss the ground state of a one-dimensional trapped Fermi gas with imbalanced spin population, for an arbitrary attractive interaction. A phase separation state, with a polarized superfluid core immersed in an unpolarized superfluid shell, emerges below a critical spin polarization. Above it, coexistence of polarized superfluid matter and a fully polarized normal gas is favored. These two exotic states could be realized experimentally in highly elongated atomic traps, and diagnosed by measuring the lowest density compressional mode. We identify the polarized superfluid as having an Fulde-Ferrell-Larkin-Ovchinnikov structure, and predict the resulting mode frequency as a function of the spin polarization.},
doi = {10.1103/PHYSREVLETT.98.070403},
journal = {Physical Review Letters},
number = 7,
volume = 98,
place = {United States},
year = {Fri Feb 16 00:00:00 EST 2007},
month = {Fri Feb 16 00:00:00 EST 2007}
}
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