BCS-BEC Crossover in a Two-Dimensional Fermi Gas

被引：146

作者：

Bertaina, G. ^{[1
,2
,3
]}

Giorgini, S. ^{[2
,3
]}

机构：

[1] Ecole Polytech Fed Lausanne, Inst Theoret Phys, CH-1015 Lausanne, Switzerland

[2] Univ Trent, Dipartimento Fis, I-38123 Povo, Italy

[3] Univ Trent, INO CNR BEC Ctr, I-38123 Povo, Italy

来源：

PHYSICAL REVIEW LETTERS | 2011年 / 106卷 / 11期

关键词：

2; DIMENSIONS; BOSE CONDENSATION; STATE;

D O I：

10.1103/PhysRevLett.106.110403

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We investigate the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluidity to Bose-Einstein condensation (BEC) in a two-dimensional Fermi gas at T = 0 using the fixed-node diffusion Monte Carlo method. We calculate the equation of state and the gap parameter as a function of the interaction strength, observing large deviations compared to mean-field predictions. In the BEC regime our results show the important role of dimer-dimer and atom-dimer interaction effects that are completely neglected in the mean-field picture. Results on Tan's contact parameter associated with short-range physics are also reported along the BCS-BEC crossover.

引用

页数：4

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