Understanding central spin decoherence due to interacting dissipative spin baths

TL;DR

This paper introduces a cluster-correlation expansion method to simulate central spin decoherence in dissipative spin baths, revealing dissipation can enhance coherence and applying it to NV centers in diamond.

Contribution

The paper presents a novel cluster-correlation expansion approach for simulating dissipative spin bath dynamics, validated against exact methods and applicable to various systems.

Findings

Dissipation can increase central spin coherence.

The method agrees well with exact simulations.

Accounting for bath dissipation is crucial for NV centers.

Abstract

We propose a new approach to simulate the decoherence of a central spin coupled to an interacting dissipative spin bath with cluster-correlation expansion techniques. We benchmark the approach on generic 1D and 2D spin baths and find excellent agreement with numerically exact simulations. Our calculations show a complex interplay between dissipation and coherent spin exchange, leading to increased central spin coherence in the presence of fast dissipation. Finally, we model near-surface NV centers in diamond and show that accounting for bath dissipation is crucial to understanding their decoherence. Our method can be applied to a variety of systems and provides a powerful tool to investigate spin dynamics in dissipative environments.