Controlling open quantum systems: Quantum correlations as resources during the transition from Markovian to non-Markovian dynamics

Abstract

In realistic quantum-mechanical systems, there will inevitably be exposure to an external environment. This exposure typically leads to Markovian processes in which the system exchanges information with its surroundings. In contrast, many quantum systems exhibit non-Markovian behavior, displaying a reverse flow of information from the environment back to the system. Controlling such open systems is crucial for various applications, including entanglement generation, dissipative quantum computation, designing quantum memories, and quantum metrology. We propose a theoretical model for a two-photon system, inspired by an all-optical experiment. This model enables control over the flow of information between the system and its environment, providing a framework for assessing non-Markovianity through measurements taken on the open system. Additionally, we investigate the measures of correlations, namely entanglement of formation and quantum discord, to quantify the quantum correlations present within the bipartite system described in the proposed model. Our findings illustrate how quantum correlations evolve during the transition from the Markovian regime to the non-Markovian regime. They highlight their potential as a valuable resource for achieving optimal control of open quantum systems.