Dynamical role of system-environment correlations in non-Markovian dynamics

TL;DR

This paper investigates how system-environment correlations influence non-Markovian quantum dynamics, establishing a fundamental link and providing bounds on state distinguishability changes, supported by a solvable spin-chain model.

Contribution

It reveals a fundamental connection between non-Markovian behavior and system-environment correlations, deriving bounds on the rate of change of state distinguishability.

Findings

Correlation development affects non-Markovian dynamics

Derived an upper bound on distinguishability change

Illustrated results with a solvable spin-chain model

Abstract

We analyse the role played by system-environment correlations in the emergence of non-Markovian dynamics. By working within the framework developed in Breuer et al., Phys. Rev. Lett. 103, 210401 (2009), we unveil a fundamental connection between non-Markovian behaviour and dynamics of system-environment correlations. We derive an upper bound to the rate of change of the distinguishability between different states of the system that explicitly depends on the development and establishment of correlations between system and environment. We illustrate our results using a fully solvable spin-chain model, which allows us to gain insight on the mechanisms triggering non-Markovian evolution.