Experimental Simulation Of Non-Markovian Effect In Quantum Channels

A real quantum system is usually considered as an open quantum system because it inevitably interacts with the environment.This interaction will lead to the decoherence of the system.This becomes a huge challenge to the efficient implementation of quantum information and quantum computing.This paper focuses on the non-Markovian process in open systems and how to simulate and research this process by experiments.This paper is divided into five chapters:In the first chapter,we introduce the research background of this paper.The main results of this paper are shown.In the second chaper,we first introduce some basic concepts of quantum information.Then,some methods that are used in the study of open systems such as master equation method and hierarchy equation method are discussed.In addition,some typical quantum channels are introduced.In chapter 3,we mainly discuss several typical measures of nonMarkovianity.In addition,we also introduce some experimental devices that are often used in simulation of linear optical experiment and several schemes of building quantum channels with these devices.The method of quantum state tomography is also introduced.In the fourth chapter,we use linear optical platform to simulate a kind of quantum channel with non-rotating wave approximation,and use this channel to simulate the quantum non-Markovian effect.Both of the quantum channels with and without rotating-wave approximaiton(RWA)are studied.With the coupling parameters changing,we find that the behavior of the non-Markovianity in the non-RWA channel is quite different from the behavior in the RWA channel,the non-RWA channel is closer to the real environment,which reveals the important role of the counter-rotating-wave terms in influencing the non-Markovianity.Chapter five is the conclusions and prospects.Chapter six is achievements during graduate study.