强热辐射环境中两能级原子量子态保真度  

Fidelity of two-level atoms' quantum states in a strong thermal radiation field

作　　者：张登玉[1] 郭萍[2] 高峰[1] 

机构地区：[1]衡阳师范学院物理系,衡阳421008 [2]南华大学数理学院,衡阳421001

出　　处：《物理学报》2007年第4期1906-1910,共5页Acta Physica Sinica

基　　金：湖南省教育厅科研基金重点项目(批准号:04A006);湖南省教育厅科研基金(批准号:03C095)资助的课题.~~

摘　　要：两个两能级原子置于强热辐射场环境中,原子用泡利算符描述,环境用无穷的谐振子热库描述,运用密度矩阵方法,得到两能级原子密度矩阵元演化规律.针对三种不同的初始状态,分析置于热辐射场中原子量子态保真度.结果表明:当两个原子初始处于不同量子叠加态时,量子信息在传输过程中可能发生部分失真,也可能不失真.The two-level atom is described by Paoli sign and the environment is described by infinite harmonic particle thermal reservoir. We have studied the problem of fidelity of quantum states of two-level atoms located in strongly thermal radiation field. The two-level atoms＇ reducible density rectangular array is obtained. We discuss the properties of fidelity. It is shown that for the two two-level atoms initially situated in different coherent superposition states, quantum information may partly lose fidelity or may not lose fidelity during evolution in transmission process.

关 键 词：热辐射场 两能级原子 保真度 消相干 

分 类 号：O431.2[机械工程—光学工程]