Decoherence of the central spin in dissipative spin baths*

Mykyta Onizhuk, Yuxin Wang, Jonah Nagura, Aashish Clerk, and Giulia Galli

 

To harness the potential of solid-state spin qubits for quantum sensing applications, it is critical to obtain a deep understanding of their intricate interactions with surface-bound spins.

This work presents a new methodology based on cluster correlation expansion to study how a central spin interacts with other spins in a dissipative bath. We tested the method on several model systems and found it faithfully reproduces reference numerical results.

Using the framework developed here, we identify a subtle interplay between dissipation and coherent spin exchange. Specifically, we find that fast dissipation in the bath can increase the coherence time of the central spin. Finally, we use our method to simulate nitrogen-vacancy (NV) centers close to a diamond surface, and we find that bath-induced dissipation is the main factor determining the NV center's decoherence in experimentally relevant regimes.

Our method holds promises to study the spin dynamics of defects in complex systems, thus providing a useful tool to understand the quantum behavior of the central spin in dissipative environments.