# Driving-induced amplification of non-Markovianity in open quantum systems evolution

## TL;DR

This paper investigates how periodic control fields can amplify non-Markovian effects in open quantum systems, revealing that weak coupling regimes benefit from increased non-Markovianity, unlike strong coupling scenarios.

## Contribution

It demonstrates that time-dependent control can significantly enhance non-Markovianity in weakly coupled quantum systems, a novel insight into quantum control of open systems.

## Key findings

- Periodic modulation increases non-Markovianity in weak coupling.
- Enhancement of non-Markovianity disappears at strong coupling.
- Control fields can reversibly influence information flow in quantum systems.

## Abstract

Non-Markovian effects arising in open quantum systems evolution have been a subject of increasing interest over the past decade. One of the most appealing features of non-Markovianity (NM) is that it captures scenarios where loss of information and coherence are reversible, and thus a temporary backflow of information from the environment to the system is possible. In this work we study the interplay between the degree of non-Markovianity and the action of time-dependent control fields in an open two-level quantum system. We find that periodical modulation of a field acting solely on the system can greatly enhance the degree of non-Markovianity with respect to the undriven case. We show that this effect is present only when the coupling between system and environment is weak. Remarkably, the enhancement disappears at strong coupling, which is usually the regime where non-Markovian effects are expected to be more pronounced.