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arXiv · 2112.06420

Excited-state optically detected magnetic resonance of spin defects in hexagonal boron nitride

Zhao Mu·Hongbing Cai·Disheng Chen·Zhengzhi Jiang·Shihao Ru·Xiaodan Lyu·Xiaogang Liu·Igor Aharonovich·Weibo Gao
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Abstract

Negatively charged boron vacancy (VB-) centers in hexagonal boron nitride (hBN) are promising spin defects in a van der Waals crystal. Understanding the spin properties of the excited state (ES) is critical for realizing dynamic nuclear polarization. Here, we report zero-field splitting in the ES of DES = 2160 MHz and an optically detected magnetic resonance (ODMR) contrast of 12% at cryogenic temperature. The ES has a g-factor similar to the ground state. The ES photodynamics is further elucidated by measuring the level anti-crossing of the VB- defects under varying external magnetic fields. In contrast to nitrogen vacancy (NV-) centers in diamond, the emission change caused by excited-state level anti-crossing (ESLAC) is more prominent at cryo-temperature than at room temperature. Our results provide important information for utilizing the spin defects of hBN in quantum technology.

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Zhao Mu, Hongbing Cai, Disheng Chen, Zhengzhi Jiang, Shihao Ru, Xiaodan Lyu, Xiaogang Liu, Igor Aharonovich, Weibo Gao. 2021-12-13. Excited-state optically detected magnetic resonance of spin defects in hexagonal boron nitride. https://doi.org/10.1103/physrevlett.128.216402

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