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arXiv · 2506.14358

Temperature dependent single- and double-quantum relaxation of negatively charged boron vacancies in hexagonal boron nitride

Lin-Ke Xie·Wei Liu·Kaiyu Huang·Nai-Jie Guo·Jun-You Liu·Yu-Hang Ma·Ya-Qi Wu·Yi-Tao Wang·Zhao-an Wang·Xiao-Dong Zeng·Jia-Ming Ren·Chun Ao·Shuo Deng·Haifei Lu·Jian-Shun Tang·Chuan-Feng Li·Guang-Can Guo
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Abstract

The negatively charged boron vacancy in two-dimensional hexagonal boron nitride has emerged as a promising candidate for quantum sensing. The coherence time of this defect spins which coherent quantum sensing resides in is limited spin-phonon interactions, while the underlying physical mechanism of the corresponding high-temperature behavior is still not fully understood. Here, we probe the single- and double-quantum relaxation rates on this center over the temperature range from 293 to 393 K. The results show that both relaxation rates increase with increasing temperature, and the double-quantum relaxation rate significantly increases rapidly. At high temperature (above 400 K), the double-quantum relaxation rate is much greater than single-quantum relaxation rate, and may dominate the decoherence channel of spin-phonon interactions. Using a theoretical model of second-order spin-phonon interactions, we attribute the high-temperature spin relaxation rates to interactions with higher-energy effective phonon mode, aiding the further understanding and guiding high-temperature sensing applications.

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Lin-Ke Xie, Wei Liu, Kaiyu Huang, Nai-Jie Guo, Jun-You Liu, Yu-Hang Ma, Ya-Qi Wu, Yi-Tao Wang, Zhao-an Wang, Xiao-Dong Zeng, Jia-Ming Ren, Chun Ao, Shuo Deng, Haifei Lu, Jian-Shun Tang, Chuan-Feng Li, Guang-Can Guo. 2025-06-17. Temperature dependent single- and double-quantum relaxation of negatively charged boron vacancies in hexagonal boron nitride. https://arxiv.org/abs/2506.14358

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