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Title: Momentum Distribution and Condensate Fraction of a Fermion Gas in the BCS-BEC Crossover

Abstract

By using the diffusion Monte Carlo method we calculate the one- and two-body density matrix of an interacting Fermi gas at T=0 in the BCS to Bose-Einstein condensate (BEC) crossover. Results for the momentum distribution of the atoms, as obtained from the Fourier transform of the one-body density matrix, are reported as a function of the interaction strength. Off-diagonal long-range order in the system is investigated through the asymptotic behavior of the two-body density matrix. The condensate fraction of pairs is calculated in the unitary limit and on both sides of the BCS-BEC crossover.

Authors:
 [1];  [2]; ;  [3];  [4];  [5]
  1. Dipartimento di Fisica and BEC-INFM, Universita di Trento, I-38050 Povo (Italy)
  2. (Russian Federation)
  3. Departament de Fisica i Enginyeria Nuclear, Campus Nord B4-B5, Universitat Politecnica de Catalunya, E-08034 Barcelona (Spain)
  4. JILA, University of Colorado, Boulder, Colorado 80309-0440 (United States)
  5. (Italy)
Publication Date:
OSTI Identifier:
20699632
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 95; Journal Issue: 23; Other Information: DOI: 10.1103/PhysRevLett.95.230405; (c) 2005 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; ATOMS; BCS THEORY; BOSE-EINSTEIN CONDENSATION; DENSITY MATRIX; FERMI GAS; FERMIONS; FOURIER TRANSFORMATION; MONTE CARLO METHOD; TWO-BODY PROBLEM

Citation Formats

Astrakharchik, G.E., Institute of Spectroscopy, 142190 Troitsk, Boronat, J., Casulleras, J., Giorgini, S., and Dipartimento di Fisica and BEC-INFM, Universita di Trento, I-38050 Povo. Momentum Distribution and Condensate Fraction of a Fermion Gas in the BCS-BEC Crossover. United States: N. p., 2005. Web. doi:10.1103/PhysRevLett.95.230405.
Astrakharchik, G.E., Institute of Spectroscopy, 142190 Troitsk, Boronat, J., Casulleras, J., Giorgini, S., & Dipartimento di Fisica and BEC-INFM, Universita di Trento, I-38050 Povo. Momentum Distribution and Condensate Fraction of a Fermion Gas in the BCS-BEC Crossover. United States. doi:10.1103/PhysRevLett.95.230405.
Astrakharchik, G.E., Institute of Spectroscopy, 142190 Troitsk, Boronat, J., Casulleras, J., Giorgini, S., and Dipartimento di Fisica and BEC-INFM, Universita di Trento, I-38050 Povo. Fri . "Momentum Distribution and Condensate Fraction of a Fermion Gas in the BCS-BEC Crossover". United States. doi:10.1103/PhysRevLett.95.230405.
@article{osti_20699632,
title = {Momentum Distribution and Condensate Fraction of a Fermion Gas in the BCS-BEC Crossover},
author = {Astrakharchik, G.E. and Institute of Spectroscopy, 142190 Troitsk and Boronat, J. and Casulleras, J. and Giorgini, S. and Dipartimento di Fisica and BEC-INFM, Universita di Trento, I-38050 Povo},
abstractNote = {By using the diffusion Monte Carlo method we calculate the one- and two-body density matrix of an interacting Fermi gas at T=0 in the BCS to Bose-Einstein condensate (BEC) crossover. Results for the momentum distribution of the atoms, as obtained from the Fourier transform of the one-body density matrix, are reported as a function of the interaction strength. Off-diagonal long-range order in the system is investigated through the asymptotic behavior of the two-body density matrix. The condensate fraction of pairs is calculated in the unitary limit and on both sides of the BCS-BEC crossover.},
doi = {10.1103/PhysRevLett.95.230405},
journal = {Physical Review Letters},
number = 23,
volume = 95,
place = {United States},
year = {Fri Dec 02 00:00:00 EST 2005},
month = {Fri Dec 02 00:00:00 EST 2005}
}
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