摘要
偶极原子间的相互作用具有长程各向异性且具有同时吸引和排斥的特点,因此偶极相互作用对偶极玻色-爱因斯坦凝聚体之间的干涉现象影响明显。本文用虚时演化方法和时间劈裂傅里叶谱方法具体研究了偶极原子极化方向对偶极凝聚体之间干涉现象的影响,当偶极原子极化矢量在凝聚体所处平面的投影方向关于两偶极凝聚体初始分割线对称时,凝聚体干涉图样也关于分割线对称,而干涉产生的涡旋手性刚好相反。当偶极原子间的相互作用各向异性时,偶极凝聚体干涉产生的涡旋分布呈现如下特征:当投影方向与初始分割线平行时,干涉不会产生涡旋,形成的干涉条纹为直线形且条纹宽度相同;当投影方向与初始分割线夹角接近π/4(或3π/4)时,在干涉图样的中心区域形成可见的沿直线分布的正(或反)涡旋结构;当投影方向与初始分割线夹角接近π/2时,中心区域会形成涡旋-反涡旋对。
More recently,Bose-Einstein condensates of atoms with long-range and anisotropic dipolar atomic interaction are studied experimentally and theoretically.The dipole-dipole interaction can be either attractive or repulsive.Therefore,it can induce various interesting phenomena,making dipolar Bose-Einstein condensates an ideal candidate for exploring a variety of novel experimental phenomena.In this paper,the interference of the dipolar Bose-Einstein condensates released from a double-well potential is investigated,and the influence of the polarization direction of dipolar atoms on the interference between dipolar Bose-Einstein condensates is studied via virtual time evolution method and time-splitting Fourier spectrum method.According to comparing the interference patterns of the different polarization direction of dipolar atoms,it’s found that,when the projection direction of the polarization vector of the dipolar atoms on the plane where the condensates is located is symmetrical about the initial parting line of the two dipolar condensates,the interference patterns are also symmetrical about the parting line,and the chirality of vortices generated in the interference process is just opposite.When the dipolar atom interaction shows obvious anisotropy,the interference patterns have the following characteristics:when the projection direction of the polarization vector is parallel to the initial parting line of the two dipolar condensates,no vortex will be generated during the interference process,the interference fringes are straight and the fringe width is the same;when the angle between the projection direction of the polarization vector and the initial parting line of the two dipolar condensates is close to π/4(or 3π/4),visible vortices(or antivortices) distributed along a straight line will be formed in the central area of the interference pattern;when the angle between the projection direction of the polarization vector and the initial parting line of the two dipolar condensates is close to π/2,vortex-antivortex pairs will be formed in the central region of the interference pattern.
作者
杨国全
靳晶晶
张素英
YANG Guo-quan;JIN Jing-jing;ZHANG Su-ying(Department of physics and Electronic Engineering,Jinzhong University,Jinzhong 030619,China;School of Science,North University of China,Taiyuan 030051,China;Institute of Theoretical Physics,Shanxi University,Taiyuan 030006,China)
出处
《量子光学学报》
北大核心
2022年第4期333-340,共8页
Journal of Quantum Optics
基金
国家自然科学基金(11772177,12104418)
山西省高等学校科技创新项目(2020L0599,2019L0551)
晋中学院引进博士科研启动基金(jzxybsjjxm2019014)。
作者简介
杨国全(1982-),男,山西应县人,讲师,主要从事超冷原子方面的研究;通信作者:张素英,E-mail:zhangsy@sxu.edu.cn。
