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arXiv · 2307.06774

Isotopic control of the boron-vacancy spin defect in hexagonal boron nitride

T. Clua-Provost·A. Durand·Z. Mu·T. Rastoin·J. Fraunié·E. Janzen·H. Schutte·J. H. Edgar·G. Seine·A. Claverie·X. Marie·C. Robert·B. Gil·G. Cassabois·V. Jacques
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Abstract

We report on electron spin resonance (ESR) spectroscopy of boron-vacancy (V$_\text{B}^-$) centers hosted in isotopically-engineered hexagonal boron nitride (hBN) crystals. We first show that isotopic purification of hBN with $^{15}$N yields a simplified and well-resolved hyperfine structure of V$_\text{B}^-$ centers, while purification with $^{10}$B leads to narrower ESR linewidths. These results establish isotopically-purified h$^{10}$B$^{15}$N crystals as the optimal host material for future use of V$_\text{B}^-$ spin defects in quantum technologies. Capitalizing on these findings, we then demonstrate optically-induced polarization of $^{15}$N nuclei in h$^{10}$B$^{15}$N, whose mechanism relies on electron-nuclear spin mixing in the V$_\text{B}^-$ ground state. This work opens up new prospects for future developments of spin-based quantum sensors and simulators on a two-dimensional material platform.

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T. Clua-Provost, A. Durand, Z. Mu, T. Rastoin, J. Fraunié, E. Janzen, H. Schutte, J. H. Edgar, G. Seine, A. Claverie, X. Marie, C. Robert, B. Gil, G. Cassabois, V. Jacques. 2023-07-13. Isotopic control of the boron-vacancy spin defect in hexagonal boron nitride. https://doi.org/10.1103/physrevlett.131.126901

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