Controllable Non-Markovianity for a Spin Qubit in Diamond

TL;DR

This paper demonstrates a controllable method to tune non-Markovian dynamics of a spin qubit in diamond by adjusting the nitrogen spin population, enabling precise quantum control and understanding of decoherence.

Contribution

It introduces a flexible scheme to actively control non-Markovianity in a spin qubit system using a nitrogen-vacancy center, with minimal data collection through Bayesian analysis.

Findings

Non-Markovianity can be smoothly tuned by changing nitrogen spin population.

Decoherence dynamics are characterized, excluding other non-Markovian sources.

Bayesian analysis enables precise parameter estimation and prediction.

Abstract

We present a flexible scheme to realize non-artificial non-Markovian dynamics of an electronic spin qubit, using a nitrogen-vacancy center in diamond where the inherent nitrogen spin serves as a regulator of the dynamics. By changing the population of the nitrogen spin, we show that we can smoothly tune the non-Markovianity of the electron spin's dynamic. Furthermore, we examine the decoherence dynamics induced by the spin bath to exclude other sources of non-Markovianity. The amount of collected measurement data is kept at a minimum by employing Bayesian data analysis. This allows for a precise quantification of the parameters involved in the description of the dynamics and a prediction of so far unobserved data points.