报告题目：Crossover Between Mon-Markovian and Markov Dynamics Induced by a Structured Environment
报 告 人：Ting Yu，Department of Physics and Engineering Physics，Stevens Institute of Technology, New Jersey, USA
报告摘要：In this talk I will report our recent work on the crossover between non-Markovian and Markov dynamics induced by a hierarchical environment. It is known that non-Markovian evolution of an open quantum system can be induced by the memory effects of a reservoir. Although a reservoir with stronger memory effects may seem like it should cause stronger non-Markovian effects on the system of interest, this seemingly intuitive thinking may not always be correct. We illustrate this by investigating a qubit (a two-level atom) that is coupled to a hierarchical environment, which contains a single-mode cavity and a reservoir consisting of infinite numbers of modes. We show how the non-Markovian character of the system is influenced by the coupling strength between the qubit and cavity and the correlation time of the reservoir. In particular, we found a new phenomenon whereby the qubit Markovian and non-Markovian transition exhibits a anomalous pattern in a parameter space depicted by the coupling strength and the correlation time of the reservoir.
In addition, I will report some recent work on the stochastic Schroedinger equations for the dynamics of an open quantum system coupled to a reservoir consisting of a finite or infinite number of bosons (or fermions).