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DOE OSTI · 1616696

Spin coherence in two-dimensional materials

Abstract

Spin defects in semiconducting solids are promising platforms for the realization of quantum bits. At low temperature and in the presence of a large magnetic field, the central spin decoherence is mainly due to the fluctuating magnetic field induced by nuclear spin flip-flop transitions. Using spin Hamiltonians and a cluster expansion method, we investigate the electron spin coherence of defects in two-dimensional (2D) materials, including delta-doped diamond layers, thin Si films, MoS 2 , and h-BN. We show that isotopic purification is much more effective in 2D than in three-dimensional materials, leading to an exceptionally long spin coherence time of more than 30 ms in an isotopically pure monolayer of MoS 2 .

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Ye, Meng, Seo, Hosung, Galli, Giulia. 2019-04-09. Spin coherence in two-dimensional materials. https://doi.org/10.1038/s41524-019-0182-3

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36 MATERIALS SCIENCE↗