Controllable non-Markovianity in phase relaxation

TL;DR

This paper presents an exact theoretical model and experimental demonstration of controllable non-Markovian dynamics in a quantum system, highlighting the importance of non-Markovian effects in quantum technology under low-temperature conditions.

Contribution

It provides the first exact solution of a non-trivial non-Markovian quantum model and demonstrates experimental control of non-Markovianity using NMR techniques.

Findings

Exact solution of a non-Markovian quantum model

Experimental control of non-Markovianity in NMR

Qualitative agreement between theory and experiment

Abstract

Recently remarkable progress in quantum technology has been witnessed. In view of this it is important to investigate an open quantum system as a model of such quantum devices. Quantum devices often require extreme conditions such as very low temperature for the devices to operate. Dynamics can be non-Markovian in such a situation in contrast with Markovian dynamics in high temperature regime. This observation necessitates us to investigate a non-Markovian open quantum system, both theoretically and experimentally. In this paper, we report two important results: 1) Exact solution of a simple but non-trivial theoretical model and 2) demonstration of this model by NMR experiments, where non-Markovianity is continuously controllable. We observe qualitative agreement between theory and experiment.