自旋轨道耦合对超冷排斥费米气体相变的影响  

Effects of the spin-orbit coupling on the phase transition of ultra cold repulsive Fermi gases

作　　者：赵华[1] 李华艳[1] 周晓凡[2] 

机构地区：[1]深圳大学物理科学与技术学院,深圳518060 [2]山西大学理论物理研究所,太原030006

出　　处：《深圳大学学报（理工版）》2014年第6期570-575,共6页Journal of Shenzhen University(Science and Engineering)

基　　金：国家自然科学基金资金项目(10774095);深圳市科技研发基金资助项目(JC201005280474A)~~

摘　　要：利用密度矩阵重整化群(density-matrix-renormalization-group,DMRG)方法,研究自旋轨道耦合和Zeeman场作用下处于一维光学晶格中的排斥费米气体的量子相变.研究表明,当自旋轨道耦合与Zeeman场共同作用于系统时,自旋轨道耦合效应将增强系统的金属性,同时削弱Zeeman场对系统的极化作用.当自旋轨道耦合作用较弱使系统保持为Mott绝缘态时,随自旋轨道耦合强度的变化,Zeeman场的极化效应使系统呈现不同的量子态.By using the density-matrix-renormalization-group（ DMRG） method,the phase transition of ultra-cold repulsive Fermi gases loaded on one-dimensional optical lattices is investigated when spin-orbit coupling（ SOC） and Zeeman field are involved. It is found that the SOC effects enhance the metal phase and reduce the polarization of the system in the presence of both the SOC and a large Zeeman field. Furthermore,when the system keeps a Mott insulation state under the weak spin orbit coupling,it is shown at different SOC strengths,the system appears as different quantum states due to the polarization effect of Zeeman field.

关 键 词：凝聚态物理 Fermi-Hubbard模型 密度矩阵重整化群 光学晶格 自旋轨道耦合 Zeeman场 Mott绝缘态 

分 类 号：O469[理学—凝聚态物理]