Relativistic BCS-BEC crossover of a two-species Fermi gas with number density asymmetry at zero temperature

被引:10
作者
Guo, Hao
Chien, Chih-Chun [1 ]
He, Yan
机构
[1] Univ Chicago, James Franck Inst, Chicago, IL 60637 USA
关键词
Diquark Bose-Einstein condensation; BCS-BEC crossover; BOSE-EINSTEIN CONDENSATION; SUPERCONDUCTIVITY; PHASE;
D O I
10.1016/j.nuclphysa.2009.03.003
中图分类号
O57 [原子核物理学、高能物理学];
学科分类号
070202 ;
摘要
We systematically study relativistic two-species fermions with tunable attractive interactions and number-density asymmetry at zero temperature. In general, a Bardeen-Cooper-Schrieffer (BCS)-Bose-Einstein condensation (BEC)-relativistic BEC (RBEC) crossover is observed. A generalized BCS ground state and its stability are analyzed. The homogeneous superfluid phase can become unstable and we consider phase separation in real space for neutral systems. In the nonrelativistic limit, our results are consistent with well-known results. In addition to a BCS-BEC crossover similar to that in the nonrelativistic case, in the strongly attractive regime gapless excitations of antifermions and a RBEC state are observed. We address how different phases respond to number density asymmetry and present predictive phase diagrams of BCS-BEC-RBEC crossover. (C) 2009 Elsevier B.V. All rights reserved.
引用
收藏
页码:83 / 98
页数:16
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