Open Quantum Dynamics: Memory Effects and Superactivation of Backflow of Information

Abstract

We investigate the divisibility properties of the tensor products Λt(1)⊗Λt(2) of open quantum dynamics Λt(1,2) with time-dependent generators. These dynamical maps emerge from a compound open system S1+S2 that interacts with its own environment in such a way that memory effects remain when the environment is traced away. This study is motivated by the following intriguing effect: one can have Backflow of Information (BFI) from the environment to S1+S2 without the same phenomenon occurring for either S1 and S2. We shall refer to this effect as the Superactivation of BFI (SBFI).