拓展的玻色—哈伯德模型中由原子对隧穿诱导的等效薛定谔猫态及其量子—经典相变（英文）  

Atom-pair Tunneling-induced Effective Schr?dinger Cat State and Its Quantum-classical Transitions in the Extended Bose-Hubbard Model

作　　者：刘吉利[1] LIU Ji-li(College of Physics and Information Engineering,Shanxi Normal University,Linfen 041000,Shanxi,China)

机构地区：[1]山西师范大学物理与信息工程学院

出　　处：《山西师范大学学报（自然科学版）》2019年第2期27-36,共10页Journal of Shanxi Normal University(Natural Science Edition)

摘　　要：在拓展的玻色-哈伯德模型的强相互作用区域里,等效薛定谔猫态也就是宏观量子态出现了.等效薛定谔猫态是二重简并的基态,是由对隧穿引起的.本文运用有效势和周期瞬子的方法研究了两个等效薛定谔猫态和它们之间的从经典到量子行为的相变.更重要的是,通过从高阶微扰得到一阶相变的标准,我们得到了完整的相图和一阶和二阶相变的边界.然后我们研究重要相变中对隧穿的影响,在强相互作用区域里,重要相变标志了对隧穿的存在,这对有关的实验研究会有很大的帮助.In the strong interaction regime,effective Schr dinger cat states(macroscopic quantum states)appear in the extended Bose-Hubbard Model,which is two-hold degenerate ground state,due to the atom-pair tunnelling.In this paper,it is investigated by a effective potential method and a periodic instanton method that effective Schr dinger cat states and its transitions from classical to quantum behavior.More importantly,by the criterion for a first-order transition derived from the high-order of perturbation theory,we can be obtain complete phase diagram and find the phase boundary between first and second-order transitions.Then we investigate the influence of atom-pair tunneling on the dominant transition process.In the strong interaction region,these transitions,due to the atom-pair tunneling,indicate the existing of atom-pair tunneling and can be of useful in the experiment investigation.

关 键 词：等效薛定谔猫态 量子-经典相变 

分 类 号：O469[理学—凝聚态物理]