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

: Liu BH, Li L, Huang YF, Li CF, Guo GC, Laine EM, Breuer HP, Piilo J

Publisher: NATURE PUBLISHING GROUP

: 2011

: Nature Physics

: NATURE PHYSICS

: NAT PHYS

: 12

: 7

: 12

: 931

: 934

: 4

: 1745-2473

DOI: https://doi.org/10.1038/NPHYS2085

Realistic quantum mechanical systems are always exposed to an external environment. This often induces Markovian processes in which the system loses information to its surroundings. However, many quantum systems exhibit non-Markovian behaviour with a flow of information from the environment back to the system(1-5). The environment usually consists of large number of degrees of freedom which are difficult to control, but some sophisticated schemes for reservoir engineering have been developed(6). The control of open systems plays a decisive role, for example, in proposals for entanglement generation(7-9) and dissipative quantum computation(10), for the design of quantum memories(11) and in quantum metrology(12). Here we report an all-optical experiment which allows one 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 measurements on the open system.