Stability of spinor Fermi gases in tight waveguides
Abstract
The two and threebody correlation functions of the ground state of an optically trapped ultracold spin(1/2) Fermi gas (SFG) in a tight waveguide [onedimensional (1D) regime] are calculated in the plane of even and oddwave coupling constants, assuming a 1D attractive zerorange oddwave interaction induced by a 3D pwave Feshbach resonance, as well as the usual repulsive zerorange evenwave interaction stemming from 3D swave scattering. The calculations are based on the exact mapping from the SFG to a 'LiebLinigerHeisenberg' model with deltafunction repulsions depending on isotropic Heisenberg spinspin interactions, and indicate that the SFG should be stable against threebody recombination in a large region of the coupling constant plane encompassing parts of both the ferromagnetic and antiferromagnetic phases. However, the limiting case of the fermionic TonksGirardeau gas, a spinaligned 1D Fermi gas with infinitely attractive pwave interactions, is unstable in this sense. Effects due to the dipolar interaction and a Zeeman term due to a resonancegenerating magnetic field do not lead to shrinkage of the region of stability of the SFG.
 Authors:
 Departamento de QuimicaFisica, Universidad del Pais Vasco, Apartado 644, 48080 Bilbao (Spain)
 College of Optical Sciences, University of Arizona, Tucson, Arizona 85721 (United States)
 Publication Date:
 OSTI Identifier:
 21011284
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 76; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.76.013615; (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; ANTIFERROMAGNETISM; CORRELATION FUNCTIONS; COUPLING CONSTANTS; FERMI GAS; FERMIONS; GROUND STATES; HEISENBERG MODEL; JJ COUPLING; MAGNETIC FIELDS; MESONS; P WAVES; S WAVES; SPIN; STABILITY; TEMPERATURE RANGE 00000013 K; THREEBODY PROBLEM; WAVEGUIDES; ZEEMAN EFFECT
Citation Formats
Campo, A. del, Muga, J. G., and Girardeau, M. D. Stability of spinor Fermi gases in tight waveguides. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.76.013615.
Campo, A. del, Muga, J. G., & Girardeau, M. D. Stability of spinor Fermi gases in tight waveguides. United States. doi:10.1103/PHYSREVA.76.013615.
Campo, A. del, Muga, J. G., and Girardeau, M. D. 2007.
"Stability of spinor Fermi gases in tight waveguides". United States.
doi:10.1103/PHYSREVA.76.013615.
@article{osti_21011284,
title = {Stability of spinor Fermi gases in tight waveguides},
author = {Campo, A. del and Muga, J. G. and Girardeau, M. D.},
abstractNote = {The two and threebody correlation functions of the ground state of an optically trapped ultracold spin(1/2) Fermi gas (SFG) in a tight waveguide [onedimensional (1D) regime] are calculated in the plane of even and oddwave coupling constants, assuming a 1D attractive zerorange oddwave interaction induced by a 3D pwave Feshbach resonance, as well as the usual repulsive zerorange evenwave interaction stemming from 3D swave scattering. The calculations are based on the exact mapping from the SFG to a 'LiebLinigerHeisenberg' model with deltafunction repulsions depending on isotropic Heisenberg spinspin interactions, and indicate that the SFG should be stable against threebody recombination in a large region of the coupling constant plane encompassing parts of both the ferromagnetic and antiferromagnetic phases. However, the limiting case of the fermionic TonksGirardeau gas, a spinaligned 1D Fermi gas with infinitely attractive pwave interactions, is unstable in this sense. Effects due to the dipolar interaction and a Zeeman term due to a resonancegenerating magnetic field do not lead to shrinkage of the region of stability of the SFG.},
doi = {10.1103/PHYSREVA.76.013615},
journal = {Physical Review. A},
number = 1,
volume = 76,
place = {United States},
year = 2007,
month = 7
}

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