Spin coherence in strongly coupled spin baths in quasi-two-dimensional layers

Understand

We investigate the spin-coherence decay of NV$^-$-spins interacting with the strongly-coupled bath of nitrogen defects in diamond layers.

• For thin diamond layers, we demonstrate that the spin-coherence times exceed those of bulk diamond, thus allowing to surpass the limit imposed by high defect concentrations in bulk.
• We show that the stretched-exponential parameter for the short-time spin-coherence decay is governed by the hyperfine interaction in the bath, thereby constraining random-noise models.
• We introduce a novel method based on the cluster-correlation expansion applied to strongly-interacting bath partitions.