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Title: Density-functional theory of strongly correlated Fermi gases in elongated harmonic traps

Abstract

Two-component Fermi gases with tunable repulsive or attractive interactions inside quasi-one-dimensional (Q1D) harmonic wells may soon become the cleanest laboratory realizations of strongly correlated Luttiger and Luther-Emery liquids under confinement. We present a microscopic Kohn-Sham density-functional theory of these systems, with specific attention to a gas on the approach to a confinement-induced Feshbach resonance. The theory employs the one-dimensional Gaudin-Yang model as the reference system and transfers the appropriate Q1D ground-state correlations to the confined inhomogeneous gas via a suitable local-density approximation to the exchange and correlation energy functional. Quantitative understanding of the role of the interactions in the bulk shell structure of the axial density profile is thereby achieved. While repulsive intercomponent interactions depress the amplitude of the shell structure of the noninteracting gas, attractive interactions stabilize atomic-density waves through spin pairing. These should be clearly observable in atomic clouds containing of the order of up to 100 atoms.

Authors:
; ;  [1];  [2];  [3]
  1. NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa (Italy)
  2. Institute for Studies in Theoretical Physics and Mathematics, Tehran 19395-5531 (Iran, Islamic Republic of)
  3. (Italy)
Publication Date:
OSTI Identifier:
20786967
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.73.033609; (c) 2006 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; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; APPROXIMATIONS; ATOMS; CONFINEMENT; DENSITY FUNCTIONAL METHOD; ELECTRON CORRELATION; FERMI GAS; FERMIONS; GROUND STATES; LIQUIDS; ONE-DIMENSIONAL CALCULATIONS; RADIATION PRESSURE; RESONANCE; SPIN; TRAPS

Citation Formats

Gao Xianlong, Polini, Marco, Tosi, M. P., Asgari, Reza, and NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa. Density-functional theory of strongly correlated Fermi gases in elongated harmonic traps. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Gao Xianlong, Polini, Marco, Tosi, M. P., Asgari, Reza, & NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa. Density-functional theory of strongly correlated Fermi gases in elongated harmonic traps. United States. doi:10.1103/PHYSREVA.73.0.
Gao Xianlong, Polini, Marco, Tosi, M. P., Asgari, Reza, and NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa. Wed . "Density-functional theory of strongly correlated Fermi gases in elongated harmonic traps". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786967,
title = {Density-functional theory of strongly correlated Fermi gases in elongated harmonic traps},
author = {Gao Xianlong and Polini, Marco and Tosi, M. P. and Asgari, Reza and NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa},
abstractNote = {Two-component Fermi gases with tunable repulsive or attractive interactions inside quasi-one-dimensional (Q1D) harmonic wells may soon become the cleanest laboratory realizations of strongly correlated Luttiger and Luther-Emery liquids under confinement. We present a microscopic Kohn-Sham density-functional theory of these systems, with specific attention to a gas on the approach to a confinement-induced Feshbach resonance. The theory employs the one-dimensional Gaudin-Yang model as the reference system and transfers the appropriate Q1D ground-state correlations to the confined inhomogeneous gas via a suitable local-density approximation to the exchange and correlation energy functional. Quantitative understanding of the role of the interactions in the bulk shell structure of the axial density profile is thereby achieved. While repulsive intercomponent interactions depress the amplitude of the shell structure of the noninteracting gas, attractive interactions stabilize atomic-density waves through spin pairing. These should be clearly observable in atomic clouds containing of the order of up to 100 atoms.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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