从混合态构造相应的系统-热库纠缠纯态的新方法  

Constructing System-thermo Environment Pure Entangled State from a Mixed State

作　　者：李兰兰 张科 范洪义[2] LI Lanlan;ZHANG Ke;FAN Hongyi(School of Electronic Engineering,Huainan Normal University,Huainan,232038 China;Department of Material Science and Engineering,University of Science and Technology of China,Hefei,230026 China)

机构地区：[1]淮南师范学院电子工程学院,安徽淮南232038 [2]中国科学技术大学材料科学与工程系,安徽合肥232006

出　　处：《低温物理学报》2019年第4期267-271,共5页Low Temperature Physical Letters

基　　金：淮南师范学院校级重点项目(批准号:2019XJZD04)资助的课题.

摘　　要：在量子统计学和低温物理学中,常用密度算符(或混合态)来表示物理系综.本文旨在提出一个新方法能将混合态转化为系统与热库相纠缠的量子纯态,这样做不但可以彰显环境对系统的影响,探寻新的物理态,尤其是纠缠态,而且能将求系综平均的复杂计算转化为较为简洁的求纯态平均.我们的新方法是将相干态和有序算符内的积分理论结合起来,就可直接将混合态扩充为自由度加倍的纯态.In quantum statistics theory and low temperature physics,we usually used are density operators(or mixed states).We propose a new approach for constructing the corresponding system-thermo environment pure entangled state from a mixed state.In this way we can not only exhibit the affection from the environment to the system,but also can find new entangled state and simplify the calculation of ensemble average to evaluating the pure state expectation value.Our new method lies in combining coherent state and the technique of integration within ordered product(IWOP)of operators.The pure entangled state is defined in real-fictitious two-mode space.

关 键 词：系统-热库纠缠纯态 混合态 有序算符内的积分理论 

分 类 号：O413[理学—理论物理]