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arXiv · 2401.16169

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

Philip Schätzle·Reyhaneh Ghassemizadeh·Daniel F. Urban·Thomas Wellens·Peter Knittel·Florentin Reiter·Jan Jeske·Walter Hahn
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Abstract

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. Our results facilitate material development for quantum-technology devices.

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Philip Schätzle, Reyhaneh Ghassemizadeh, Daniel F. Urban, Thomas Wellens, Peter Knittel, Florentin Reiter, Jan Jeske, Walter Hahn. 2024-01-29. Spin coherence in strongly coupled spin baths in quasi-two-dimensional layers. https://doi.org/10.1103/physrevb.110.l220302

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