Abstract
Jyrki Piilo (Uniersity of Turku, Finland)
Quantum decoherence and memory effects in open quantum systems
Realistic quantum systems are always exposed to an external environment. The presence of the environment often gives rise to decoherence and Markovian process in which the system loses information to its surroundings. However, many quantum systems exhibit a pronounced non-Markovian behavior signifying the presence of quantum memory effects. In this talk, we show how to quantify non-Markovianity of a process based on the concept of information flow, and how to control the transition from Markovian to non-Markovian quantum dynamics with memory effcts in an optical system. Moreover, we also show that an open system can exploit information initially held by its environment, i.e. initial correlations in a composite environment can lead to a nonlocal open system dynamics which exhibits strong memory effects. The latter results also demonstrate that in an optical setup, the polarization degree of freedom of photons can be designed to act as a quantum probe for their frequency correlations.