论文标题
独立的非Markmarkovian浴室中耦合量子振荡器的纠缠动力学
Entanglement dynamics of coupled quantum oscillators in independent nonMarkovian baths
论文作者
论文摘要
这项工作旨在更好地了解开放量子系统中的纠缠是如何由两个耦合的布朗振荡器代表的，受到非牛奶环境（带有记忆）的影响，此处由两个独立浴缸分别与之相互作用。我们考虑两种设置，即一种“对称”配置，其中振荡器及其浴室的参数都是相同的，并且是一种“非对称”配置，其中它们与众不同，尤其是“混合”配置，其中两个振荡器之一与非Marksovian Bath和Markovian相互作用。我们问两组问题：Q1）Bath的非Marksovianity在哪个时间制度最大的纠缠使该系统受益？ The answers we get from detailed numerical studies suggest that A1) For an initially entangled pair of oscillators, we see that in the intermediate time range, the duration of entanglement is proportional to the memory time, and it lasts a fraction of the relaxation time, but at late times when the dynamics reaches a steady state, the value of the symplectic eigenvalue of the partially transposed covariance matrix barely benefit from the bath非标记性。对于第二组问题：Q2）一个非马克维亚浴室的记忆可以传递给另一个马尔可夫浴场吗？如果是这样，这种内存转移是否有助于维持系统的纠缠动态？我们来自不对称混合配置的数值研究的结果表明，A2）当记忆时间较短的系统耦合到具有较长内存时间的另一个系统时，它可以获得改进，但以后者的成本为代价。双方纠缠的可持续性取决于最容易折断纠缠的一方。
This work strives to better understand how the entanglement in an open quantum system, here represented by two coupled Brownian oscillators, is affected by a nonMarkovian environment (with memories), here represented by two independent baths each oscillator separately interacts with. We consider two settings, a `symmetric' configuration wherein the parameters of both oscillators and their baths are identical, and an `asymmetric' configuration wherein they are different, in particular, a `hybrid' configuration, where one of the two coupled oscillators interacts with a nonMarkovian bath and the other with a Markovian bath. We ask two groups of questions: Q1) Which time regime does the bath's nonMarkovianity benefit the system's entanglement most? The answers we get from detailed numerical studies suggest that A1) For an initially entangled pair of oscillators, we see that in the intermediate time range, the duration of entanglement is proportional to the memory time, and it lasts a fraction of the relaxation time, but at late times when the dynamics reaches a steady state, the value of the symplectic eigenvalue of the partially transposed covariance matrix barely benefit from the bath nonMarkovianity. For the second group of questions: Q2)Can the memory of one nonMarkovian bath be passed on to another Markovian bath? And if so, does this memory transfer help to sustain the system's entanglement dynamics? Our results from numerical studies of the asymmetric hybrid configuration indicate that A2) A system with a short memory time can acquire improvement when it is coupled to another system with a long memory time, but, at a cost of the latter. The sustainability of the bipartite entanglement is determined by the party which breaks off entanglement most easily.
