高磁场下7Li原子的d波Feshbach共振  

d-wave Feshbach resonance of 7Li atoms in high magnetic fields

作　　者：陈钟之 赖海健 齐燃 俞振华 CHEN Zhongzhi;LAI Haijian;QI Ran;YU Zhenhua(School of Physics and Astronomy,Sun Yat-Sen University,Zhuhai 519082,China;Department of Physics,Renmin University of China,Beijing 100872,China)

机构地区：[1]中山大学物理与天文学院,珠海519082 [2]中国人民大学物理系,北京100872

出　　处：《物理学报》2025年第9期250-256,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12474270)资助的课题.

摘　　要：Feshbach共振是在特定外场下原子间发生共振相互作用的现象,主要表现为在共振附近量化低能散射性质的广义散射长度随外场趋于发散.近年来,随着冷原子物理的发展,s波及高分波的Feshbach共振相继被发现,为研究共振相互作用在多体物理中的效应提供了宝贵的途径.本文基于多通道量子缺陷理论(MQDT),预言在1039.24和1055.64 G(1 G=10^(-4)T)外磁场下,7Li原子间存在两个d波Feshbach共振,并确定了共振的各项参数,如共振宽度等.同时,估计了磁偶极矩相互作用对这两个共振的影响.本文的结果拓展了在7Li原子气体中研究d波共振相互作用的契机.Feshbach resonance is a fundamental phenomenon in cold atomic physics,where interatomic interactions can be precisely changed into a scattering resonance by varying an external magnetic field.This effect plays a crucial role in ultracold atomic experiments,enabling the control of interaction strength,the formation of molecular bound states,and the realization of strongly correlated quantum systems.With the rapid development of cold atom experiments,numerous Feshbach resonances corresponding to different partial waves,such as s-wave,p-wave,and even higher partial wave ones,have been experimentally identified.While s-wave resonances have been widely utilized due to their isotropic nature and strong coupling,and higher partial-wave resonances(including p-wave and d-wave resonances),provide unique opportunities for exploring anisotropic interactions and novel quantum phases.In this study,by using the multichannel quantum defect theory(MQDT),we predict that two d-wave Feshbach resonances are existent in ^(7)Li at 1039.24 G and 1055.64 G,repectively.Physical properties of the two resonances are presented,such as the resonance width and closed channel dimer energy.In addition,we optimize the computational parameters by using the Nelder-Mead algorithm and investigate the possible resonance splitting induced by dipole-dipole interactions in higher partial waves.The presence of these d-wave resonances at high magnetic fields provides a new platform for investigating the interplay between higher-order partial wave interactions and quantum many-body effects.Our results provide opportunities for investigating the effects of higher partial wave Feshbach resonances in high magnetic fields.Our theoretical predictions thus serve as a useful reference for future experimental studies of higher-order resonance phenomena in lithium and other atomic species.

关 键 词：FESHBACH 共振 多通道量子缺陷理论 

分 类 号：O562[理学—原子与分子物理]