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Title: BCS-BEC crossover in a relativistic superfluid and its significance to quark matter

Abstract

The character change of a superfluid state due to the variation of the attractive force is investigated in the relativistic framework with a massive fermion. Two crossovers are found. One is a crossover from the usual BCS state to the Bose-Einstein condensation (BEC) of bound fermion pairs. The other is from the BEC to the relativistic Bose-Einstein condensation (RBEC) of nearly massless bound pairs where antiparticles as well as particles dominate the thermodynamics. Possible realization of the BEC and RBEC states in the quark matter is also pointed out.

Authors:
 [1];  [2]
  1. Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan)
  2. Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
Publication Date:
OSTI Identifier:
20713882
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 72; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.72.096004; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANTIPARTICLES; BCS THEORY; BOSE-EINSTEIN CONDENSATION; FERMIONS; QUARK MATTER; RELATIVISTIC RANGE; SUPERFLUIDITY; THERMODYNAMICS

Citation Formats

Nishida, Yusuke, and Abuki, Hiroaki. BCS-BEC crossover in a relativistic superfluid and its significance to quark matter. United States: N. p., 2005. Web. doi:10.1103/PhysRevD.72.096004.
Nishida, Yusuke, & Abuki, Hiroaki. BCS-BEC crossover in a relativistic superfluid and its significance to quark matter. United States. doi:10.1103/PhysRevD.72.096004.
Nishida, Yusuke, and Abuki, Hiroaki. Tue . "BCS-BEC crossover in a relativistic superfluid and its significance to quark matter". United States. doi:10.1103/PhysRevD.72.096004.
@article{osti_20713882,
title = {BCS-BEC crossover in a relativistic superfluid and its significance to quark matter},
author = {Nishida, Yusuke and Abuki, Hiroaki},
abstractNote = {The character change of a superfluid state due to the variation of the attractive force is investigated in the relativistic framework with a massive fermion. Two crossovers are found. One is a crossover from the usual BCS state to the Bose-Einstein condensation (BEC) of bound fermion pairs. The other is from the BEC to the relativistic Bose-Einstein condensation (RBEC) of nearly massless bound pairs where antiparticles as well as particles dominate the thermodynamics. Possible realization of the BEC and RBEC states in the quark matter is also pointed out.},
doi = {10.1103/PhysRevD.72.096004},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 72,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
  • We study the relativistic BCS-BEC crossover within a class of Nambu-Jona-Lasinio type models, including arbitrary Lorentz-scalar pairing channels. Using the mean-field approximation we investigate spectral properties of the collective bosonic excitations in the superfluid phase, with particular attention to the Nambu-Goldstone bosons of the broken symmetry. This is a first step towards a systematic improvement of the mean-field approximation by including the fluctuation effects. The general results are illustrated on pairing in dense two-flavor quark matter--the two-flavor color superconductor.
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