BCS-BEC crossover in a quasi-two-dimensional Fermi superfluid

被引：0

作者：

Zhou, Jing ^{[1
]}

Shi, Tingting ^{[2
]}

Liu, Xia-Ji ^{[3
]}

Hu, Hui ^{[3
]}

Zhang, Wei ^{[2
,4
,5
]}

机构：

[1] Chongqing Univ Posts & Telecommun, Dept Sci, Chongqing 400065, Peoples R China

[2] Renmin Univ China, Beijng Key Lab Optoelect Funct Mat & Micronano Dev, Dept Phys, Beijing 100872, Peoples R China

[3] Swinburne Univ Technol, Ctr Quantum Technol Theory, Melbourne, Vic 3122, Australia

[4] Beijing Acad Quantum Informat Sci, Beijing 100193, Peoples R China

[5] Renmin Univ China, Key Lab Quantum State Construct & Manipulat, Minist Educ, Beijing 100872, Peoples R China

来源：

NEW JOURNAL OF PHYSICS | 2023年 / 25卷 / 08期

基金：

北京市自然科学基金; 中国国家自然科学基金;

关键词：

BCS-BEC crossover; quasi-two-dimensional superfluid; Gaussian pair fluctuation; BOSE-CONDENSATION; SUPERCONDUCTIVITY; GAS; EVOLUTION;

D O I：

10.1088/1367-2630/ace98f

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We study the crossover from the Bardeen-Cooper-Shrieffer regime to the Bose-Einstein-condensation regime in an anisotropic trapped quantum gas of ultracold fermionic atoms. Using an effective two-dimensional Hamiltonian with renormalized interactions between atoms and dressed molecules, we extend the Gaussian pair fluctuation theory to quasi-two-dimensional systems. The equation of state, pair size and sound velocity as well as the convexity parameters of the Goldstone mode are investigated to show how Fermi superfluidity is affected by reduced dimensionality and Gaussian fluctuations at zero temperature in a wide range of crossover. We compare our results with the recent experiment of Li-6 atomic gases and find good agreements.

引用

页数：11

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