报告题目：Control of quantum environment: transition from Markovian to non-Markovian
摘 要：Realistic quantum mechanical systems are always exposed to an external environment. The presence of the environment often gives rise to a Markovian process in which the system loses information to its surroundings. However, many quantum systems exhibit a pronounced non-Markovian behavior in which there is a flow of information from the environment back to the system, signifying the presence of quantum memory effects. The environment is usually composed of a large number of degrees of freedom which are difficult to control, but some sophisticated schemes for modifying the environment have been developed. The physical realization and control of dynamical processes in open quantum systems plays a decisive role, for example, in recent proposals for the generation of entangled states, for schemes of dissipative quantum computation, for the design of quantum memories and for the enhancement of the efficiency in quantum metrology. Here we report an experiment which allows through selective preparation of the initial environmental states to drive the open system from the Markovian to the non-Markovian regime, to control the information flow between the system and the environment, and to determine the degree of non-Markovianity by direct measurements on the open system.
柳必恒，男，湖北武穴人。1998年考入中国科技大学物理系，2002年获物理学学士学位，2007年获光学博士学位，随后在中国科技大学从事博士后研究，现为该校光学与光学工程系副教授。研究领域为量子光学与量子信息学，近年来在多光子干涉、多光子纠缠态制备与应用以及量子信道等方向做出了一系列工作，在Nature子刊、Phys. Rev. Lett. 等刊物上发表论文二十余篇。