New Journal of Physics

Switching quantum memory on and off

Rosario Lo Franco

Published Aug 27, 2015• 32 citations

Abstract

Modifying the Markovian (memoryless) or non-Markovian (memory-keeping) nature of the environment-induced evolution of an open quantum system is crucial in quantum information theory, because it is linked to quantum memory control. A recent work (Brito and Werlang 2015 New J. Phys. 17 072001 ) shows that such a goal can be achieved without operating on unaccessible environmental features. In fact, transitions between Markovian and non-Markovian regimes of a qubit dynamics can be induced on demand if the qubit is coupled to a controlled auxiliary system. This is a step towards the improvement of quantum devices, aiming at exploiting dynamical memory effects by an external control.

DOI: 10.1088/1367-2630/17/8/081004

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