非马尔科夫环境中Werner态的量子非局域关联检验研究

Quantum non-local correlation testing of Werner state in non-Markovian environment

以量子信息领域中常使用的Werner态为研究对象,详细地研究了其在两种非马尔科夫相位阻尼环境,即Random-Telegraph(RT)噪声环境、Ornstein-Uhlenbeck(OU)噪声环境,以及非马尔科夫振幅阻尼(AD)环境中演化后的量子非局域关联检验情况.分别推导了Werner态在RT,OU以及AD环境中密度矩阵随时间的演化结果.基于Clauser-Horne-Shimony-Holt(CHSH)不等式,对演化后的量子态进行了详细的量子非局域关联检验研究.结果表明,Werner态在RT噪声环境和AD环境中存在信息回流现象,导致其量子非局域关联特性存在周期性振荡变化的现象,即随演化时间的增加,量子态能够从不具备量子非局域关联特性重新回到具有量子非局域关联特性的情况.而在OU噪声环境中,由于不存在信息回流现象,量子非局域关联检验值将随演化时间的增加而降低.同时,本文还详细给出了Werner的保真度、量子态与非马尔科夫环境的耦合强度、OU噪声环境和AD环境的线宽、RT环境噪声的翻转率等参数与成功进行量子非局域关联检验的演化时间之间的关系.

Research on whether quantum states retain quantum non-local correlation properties after evolving in non-Markovian environments has significant applications in the field of quantum information.In this work,we investigate the density matrix of quantum states evolving with time in various non-Markovian environments.Specifically,we examine two types of non-Markovian phase damping environments,namely random telegraph(RT)noise environment and Ornstein-Uhlenbeck(OU)noise environment,and non-Markovian amplitude damping(AD)environment.By utilizing the Clauser-Horne-Shimony-Holt(CHSH)inequality,a quantum non-local correlation testing of the Werner state after its evolution in these non-Markovian environments is conducted.The results show significant differences in the quantum non-local correlation testing results of the Werner state after evolving in different non-Markovian environments.Notably,the Werner state displays information backflow in the RT noise environment and the AD environment,resulting in periodic oscillations in its quantum non-local correlation testing.This suggests that under certain conditions,the quantum state can transition from a state without quantum non-local correlation back to a state with such a correlation as evolution time progresses.The results also show that the Werner state exhibits the information about backflow phenomena in RT noise environment and AD environment,leading to periodic oscillations in its quantum nonlocal correlation testing.Furthermore,these periods are inversely proportional to certain parameters,such as■and■.On the contrary,in the OU noise environment,no information about backflow is obtained,thereby leading the value of the quantum non-local correlation test to increase with evolution time increasing.In most of AD and OU noise environments,there exists a specific maximum evolution time γtmax in which successful quantum non-local correlation testing can be conducted.This maximum evolution time γtmax shows a nonlinear variation with fidelity increasing and an inverse variation with parameter increasing.In comparison,the maximum evolution time for successful quantum non-local correlation testing in the OU noise environment exceeds that in the AD environment under the same conditions,indicating that the AD environment exerts a more pronounced weakening effect on the quantum non-local correlation properties of the Werner state.