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arXiv · 1109.2677

Experimental control of the transition from Markovian to non-Markovian dynamics of open quantum systems

Bi-Heng Liu·Li Li·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Elsi-Mari Laine·Heinz-Peter Breuer·Jyrki Piilo
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Abstract

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 [1-5]. 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 [6]. 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 [7-9], for schemes of dissipative quantum computation [10], for the design of quantum memories [11] and for the enhancement of the efficiency in quantum metrology [12]. 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.

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Bi-Heng Liu, Li Li, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Elsi-Mari Laine, Heinz-Peter Breuer, Jyrki Piilo. 2011-09-13. Experimental control of the transition from Markovian to non-Markovian dynamics of open quantum systems. https://doi.org/10.1038/nphys2085

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