非对称自旋-轨道耦合系统的多体量子相干含时演化  

Dynamics of multipartite quantum coherence in asymmetric spin-orbit coupled system

作　　者：邵雅婷 严凯[1] 吴银忠 郝翔 Shao Ya-Ting;Yan Kai;Wu Yin-Zhong;Hao Xiang(School of Physical Science and Technology,Suzhou University of Science and Technology,Suzhou 215009,China)

机构地区：[1]苏州科技大学物理科学与技术学院,苏州215009

出　　处：《物理学报》2021年第1期222-228,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61875145);江苏省“十三五”重点培育学科建设基金(批准号:20168765)资助的课题.

摘　　要：本文以具有非对称性自旋相互作用的三体自旋系统为研究对象,重点研究了三体量子相干含时演化规律.采用精确量子对角化和基于量子主方程的数值模拟方法,讨论了三体量子系统中多种量子相干组分及其退相干.研究发现,量子相干组分的含时演化与整个系统的初态量子特性紧密相关.当初态为可分离纯态时,在较短时间内,非对称相互作用有利于增加多体量子相干度.这些量子相干度因受噪声影响而逐渐衰减.当初态为类Werner态时,量子相干度的分布满足加和性,即三体量子相干度等于所有两体量子相干度之和.自旋之间非对称相互作用和环境噪声都会引起三体量子相干度大于所有两体量子相干度之和.这些结论有助于多体量子资源的制备.The time evolution of multipartite quantum coherence is studied in a three-body spin system with an asymmetric interaction.The l1 norm measurement is used to estimate the degree of quantum coherence in the spin system.The decoherence of all components of quantum coherence in the three-body spin system is analyzed by the exact diagnolization and numerical method based on quantum master equation.The environmental noise induced by the spontaneous decay can be simulated by the quantum amplitude damping model.It is found that the time evolution of quantum coherence component is closely related to the quantum property of the whole initial state.When the initial state is a separable pure one,the asymmetric interactions can conduce to the enhancement of the degree of multipartite quantum coherence in a short time interval.Under the influence of quantum noise,the degree of quantum coherence decreases gradually.We pay much attention to the spatial distribution of the degree of quantum coherence in a many-body system.The additivity relationship of bipartite component and tripartite coherence can exist if the initial state is chosen to be a Werner-like state.This kind of the coherence additivity between all bipartite components and global coherence can be extended to an arbitrary N-body Werner-like state.But this additivity relationship depends on the l1 norm coherence measurement.Owing to the asymmetric interaction and noise,the degree of tripartite quantum coherence is more than the sum of all degrees of bipartite quantum coherence.The difference between the degree of tripartite coherence and the sum of all degrees of bipartite coherence is increased in a short time interval.The environmental noise can also suppress the difference in the coherence degree.The degree of the nearest neighboring bipartite coherence decreases more quickly than those of other bipartite coherences.The asymmetric interaction gives rise to the improvement in the degree of bipartite coherence and tripartite coherence.The coherence of the next-neares

关 键 词：多体量子相干 非对称自旋系统 量子退相干 量子主方程 

分 类 号：O413[理学—理论物理]