自旋张量-动量耦合玻色-爱因斯坦凝聚的动力学性质  

Dynamics of spin-tensor-momentum coupled Bose-Einstein condensates

作　　者：邱旭[1] 王林雪 陈光平[3] 胡爱元[1] 文林[1] Qiu Xu;Wang Lin-Xue;Chen Guang-Ping;Hu Ai-Yuan;Wen Lin(College of Physics and Electronic Engineering,Chongqing Normal University,Chongqing 401331,China;Department of Physics,Shaanxi University of Science and Technology,Xi’an 710021,China;Intelligent Manufacturing Industry Technology Research Institute,Sichuan University of Art and Science,Dazhou 635000,China)

机构地区：[1]重庆师范大学物理与电子工程学院,重庆401331 [2]陕西科技大学物理系,西安710021 [3]四川文理学院智能制造产业技术研究院,达州635000

出　　处：《物理学报》2023年第18期144-151,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12175027,11875010,12005125,12075163);重庆市自然科学基金(批准号:cstc2019jcyj-msxmX0217,cstc2021jcyj-msxmX0168)资助的课题。

摘　　要：利用高斯变分近似及基于Gross-Pitaevskii方程的数值求解,研究了一维自旋张量-动量耦合玻色-爱因斯坦凝聚中平面波态的动力学性质,发现基态为双轴向列态,其动量随Raman耦合强度的增加而单调递减.在微扰作用下,基态具有动力学稳定性,且展现出3种不同的谐振模激发,激发频率与Raman耦合强度、谐振子势阱的纵横比及相互作用强度有关.通过数值求解变分参数满足的运动方程和Gross-Pitaevskii方程,发现体系随时间演化将展现出周期性振荡行为.We investigate the dynamics of the plane wave state in one-dimensional spin-tensor-momentum coupled Bose-Einstein condensate.By using the Gaussian variational approximation,we first derive the equations of motion for the variational parameters,including the center-of-mass coordinate,momentum,amplitude,width,chirp,and relative phase.These variational parameters are coupled together nonlinearly by the spin-tensor-momentum coupling,Raman coupling,and the spin-dependent atomic interaction.By minimizing the energy with respect to the variational parameters,we find that the ground state is a biaxial nematic state,the momentum of the ground state decreases monotonically with the increase of the strength of the Raman coupling,and the parity of real part of the ground-state wave function is opposite to that of the imaginary part.The linear stability analysis shows that the ground state is dynamically stable under a perturbation,and exhibits three different oscillation excitation modes,the frequencies of which are related to the strength of the Raman coupling,the aspect ratio of the harmonic trap,and the strength of the atomic interaction.By solving the equations of motion for the variational parameters,we find that the system displays periodical oscillation in the dynamical evolution.These variational results are also confirmed by the direct numerical simulations of the Gross-Pitaevskii equations,and these findings reveal the unique properties given by the spin-tensor-momentum coupling.

关 键 词：自旋张量-动量耦合 玻色-爱因斯坦凝聚 GROSS-PITAEVSKII方程 

分 类 号：O469[理学—凝聚态物理]