Fermi超流气体在unitarity区域和Bose-Einstein凝聚区域的自俘获现象研究  

The self-trapping of superfluid Fermi gases in the Bose-Einstein condensation regime and in unitarity

作　　者：王文元[1] 杨阳[1] 蒙红娟[1] 马莹[1] 祁鹏堂[1] 马云云[1] 段文山[1] 

机构地区：[1]西北师范大学物理与电子工程学院,甘肃省原子分子物理与功能材料重点实验室,兰州730070

出　　处：《物理学报》2012年第10期15-21,共7页Acta Physica Sinica

基　　金：国家重点基础研究计划(批准号:2007CB814800;2011CB921503);国家自然科学基金(批准号:10725521;91021021;10875098);西北师范大学自然科学基金(批准号:NWNU-KJCXGC-03-48)资助的课题~~

摘　　要：在平均场理论和两模近似下,通过观察布居数差随时间的演化,以及布居数差的平均随非线性相互作用参数的变化,研究了对称双势阱以及势阱问高频调制时Fermi超流气体在unitarity区域和Bose-Einstein凝聚区域的自俘获现象.给出了出现自俘获现象的边界条件;发现高频调制在一定调制范围内使自俘获现象更容易实现.最后研究了初值对自俘获的影响,发现初值的绝对值|s(0)|的增加更有利于自俘获的实现.In the mean-field theory and two-mode approximation, we study the self-trapping of superfluid Fermi gases in the BEC regime and in unitarity by observing the evolution of the population imbalance with time and the variation of the average of population imbalance with several non-linear interaction parameters. The high-frequency modulations of both the symmetric double-well potential and the potential well are studied. The boundary conditions of the self-trapping and non-self-trapping are given. We find that high-frequency modulation in a certain range of modulation can make the self-trapping phenomenon easier to achieve. Finally, we study the influence of the initial value on self-trapping, and find that the increase of the absolute of the initial value can make the self-trapping more conducive to the realization.

关 键 词：BOSE-EINSTEIN凝聚 俘获 气体 超流 平均场理论 相互作用参数 高频调制 布居数差 

分 类 号：O512[理学—低温物理]