Measuring non-Markovianity of processes with controllable system-environment interaction
Key Laboratory of Quantum Information, University of Science and Technology of China CAS Hefei, 230026, China
2 Physikalisches Institut, Universität Freiburg - Hermann-Herder-Strasse 3, D-79104 Freiburg, Germany, EU
3 Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku FI-20014 Turun yliopisto, Finland, EU
Accepted: 21 November 2011
Non-Markovian processes have recently become a central topic in the study of open quantum systems. We realize experimentally non-Markovian decoherence processes of single photons by combining time delay and evolution in a polarization-maintaining optical fiber. The experiment allows the identification of the process with strongest memory effects as well as the determination of a recently proposed measure for the degree of quantum non-Markovianity based on the exchange of information between the open system and its environment. Our results show that an experimental quantification of memory in quantum processes is indeed feasible which could be useful in the development of quantum memory and communication devices.
PACS: 03.65.Yz – Decoherence; open systems; quantum statistical methods / 42.50.-p – Quantum optics / 03.67.-a – Quantum information
© EPLA, 2012