  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.

Quantum Physics