非马尔科夫环境下依赖于纯度的纠缠制备

摘要

We consider the model of two uncoupled qubits system interacting with a common zero-temperature non-Markovian reservoir. For an initially factorized two-qubit mixed state, the entanglement can be induced by non-Markovian environment. And its value is highly dependent on the initial purity of the system. Moreover, the entanglement induced by non-Markovian reservoir is much larger than that induced by Markovian reservoir. The maximal value of the induced entanglement increases with the increasing of detuning. The study shows that highly entangled states which are essential to implement some quantum information processing, can be induced by increasing the detuning between the system and the non-Markovian reservoir.%考虑了两个无相互作用的量子比特系统和一个处于零温非马尔科夫库耦合的情况。研究发现，当系统初始处于两体可分离混合态时，非马尔科夫环境可以诱导两量子比特间的纠缠，其值的大小高度依赖于体系所处态的初始纯度。此外，非马尔科夫库诱导的纠缠远大于马尔科夫库诱导的纠缠，并且随着失谐量的增大，诱导纠缠的最大值会大幅度增加。研究表明，在非马尔科夫情况下，可以通过增大系统与非马尔科夫库之间的失谐量制备量子比特间的高度纠缠态，进而完成量子信息处理的任务。