Pairing effects in the nondegenerate limit of the two-dimensional Fermi gas

被引:37
作者
Barth, Marcus [1 ]
Hofmann, Johannes [2 ]
机构
[1] Tech Univ Munich, Dept Phys, D-85748 Garching, Germany
[2] Univ Maryland, Dept Phys, Condensed Matter Theory Ctr, College Pk, MD 20742 USA
来源
PHYSICAL REVIEW A | 2014年 / 89卷 / 01期
关键词
PSEUDOGAP; BEHAVIOR;
D O I
10.1103/PhysRevA.89.013614
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
The spectral function of a spin-balanced two-dimensional Fermi gas with short-range interactions is calculated by means of a quantum cluster expansion. Good qualitative agreement is found with a recent experiment by Feld et al. [Nature (London) 480, 75 (2011)]. The effects of pairing are clearly visible in the density of states, which displays a suppression of spectral weight due to the formation of a two-body bound state. In addition, the momentum distribution and the radio-frequency spectrum are derived, which are in excellent agreement with exact universal results. It is demonstrated that in the limit of high temperature, the quasiparticle excitations are well defined, allowing for a kinetic description of the gas.
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页数:10
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