文献类型：期刊文献

英文题名：BCS-BEC crossover in spin-orbit-coupled two-dimensional Fermi gases

作者：Chen, Gang[1,2,3];Gong, Ming[1];Zhang, Chuanwei[1]

机构：[1]Washington State Univ, Dept Phys & Astron, Pullman, WA 99164 USA;[2]Shaoxing Univ, Dept Phys, Shaoxing 312000, Peoples R China;[3]Shanxi Univ, Coll Phys & Elect Engn, State Key Lab Quantum Opt & Quantum Opt Devices, Taiyuan 030006, Peoples R China

年份：2012

卷号：85

期号：1

外文期刊名：PHYSICAL REVIEW A

收录：SCI-EXPANDED(收录号：WOS:000298860400013)、、EI(收录号：20120214671830)、Scopus(收录号：2-s2.0-84855464246)、WOS

基金：We thank Yongping Zhang, Li Mao, and Wei Yi for helpful discussion. This work is supported by DARPA-YFA (Grant No. N66001-10-1-4025), ARO (Grant No. W911NF-09-1-0248), NSF (Grant No. PHY-1104546), and AFOSR (Grant No. FA9550-11-1-0313). G.C. is also supported by the 973 Program under Grant No. 2012CB921603, the NNSFC under Grant No. 11074154, and the ZJNSF under Grant No. Y6090001.

语种：英文

外文关键词：Atoms - Binding energy - Chemical potential - Electron gas - Fermions - Gases - Ground state - Spin orbit coupling

外文摘要：The recent experimental realization of spin-orbit coupling for ultracold atoms has generated much interest in the physics of spin-orbit-coupled degenerate Fermi gases. Although recently the BCS-BEC crossover in three-dimensional (3D) spin-orbit-coupled Fermi gases has been intensively studied, the corresponding two-dimensional (2D) crossover physics has remained unexplored. In this paper, we investigate, both numerically and analytically, the BCS-BEC crossover physics in 2D degenerate Fermi gases in the presence of the Rashba type of spin-orbit coupling. We derive the mean-field gap and atom-number equations suitable for 2D spin-orbit-coupled Fermi gases and solve them numerically and self-consistently, from which the dependence of the ground-state properties (chemical potential, superfluid pairing gap, ground-state energy per atom) on the system parameters (e. g., binding energy, spin-orbit-coupling strength) is obtained. Furthermore, we derive analytical expressions for these ground-state quantities, which agree well with our numerical results within a broad parameter region. Such analytical expressions also agree qualitatively with previous numerical results for 3D spin-orbit-coupled Fermi gases, where analytical results are lacking. We show that, with increasing spin-orbit coupling (SOC) strength, the chemical potential is shifted by a constant determined by the SOC strength. The superfluid pairing gap is enhanced significantly in the BCS limit for strong SOC, but increases only slightly in the BEC limit.