相位扩散通道中密度算符相关态的时间演化

The time evolution of relative density operator in phase diffusion channels

利用热纠缠态的性质,对具有代表性的相位扩散主方程进行求解,得到关于密度算符的算符和表示形式,分析不同初始态下的密度算符的时间演化结果,发现在相位扩散通道下当初始态为粒子数态或热态时密度算符保持恒定,而当初始态为相干态时系统在发生相扩散的同时始终保持相干态特性不变.

By virtue of the properties of thermal entanglement,we successfully obtain the solution to the representative phase diffusion master equation and give the operator sum representation of density operator.Having analyzed the time evolution process of density operator in different initial states,we find out that the density operators keep invariable during the initial state turning into Fock state or thermal state.But the system always maintains coherence during phase diffusion when the initial state is coherent state.