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arXiv · 2106.07697

Memory effects in quantum dynamics modelled by quantum renewal processes

Nina Megier·Manuel Ponzi·Andrea Smirne·Bassano Vacchini
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Abstract

Simple, controllable models play an important role to learn how to manipulate and control quantum resources. We focus here on quantum non-Markovianity and model the evolution of open quantum systems by quantum renewal processes. This class of quantum dynamics provides us with a phenomenological approach to characterise dynamics with a variety of non-Markovian behaviours, here described in terms of the trace distance between two reduced states. By adopting a trajectory picture for the open quantum system evolution, we analyse how non-Markovianity is influenced by the constituents defining the quantum renewal process, namely the time-continuous part of the dynamics, the type of jumps and the waiting time distributions. We focus not only on the mere value of the non-Markovianity measure, but also on how different features of the trace distance evolution are altered, including times and number of revivals.

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Nina Megier, Manuel Ponzi, Andrea Smirne, Bassano Vacchini. 2021-06-14. Memory effects in quantum dynamics modelled by quantum renewal processes. https://doi.org/10.3390/e23070905

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