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arXiv · 2212.02849

Temperature-dependent behaviors of single spin defects in solids determined with Hz-level precision

Shaoyi Xu·Mingzhe Liu·Tianyu Xie·Zhiyuan Zhao·Qian Shi·Pei Yu·Chang-Kui Duan·Fazhan Shi·Jiangfeng Du
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Abstract

Revealing the properties of single spin defects in solids is essential for quantum applications based on solid-state systems. However, it is intractable to investigate the temperature-dependent properties of single defects, due to the low precision for single-defect measurements in contrast to defect ensembles. Here we report that the temperature dependence of the Hamiltonian parameters for single negatively charged nitrogen-vacancy (NV$^{-}$) centers in diamond is precisely measured, and the results find a reasonable agreement with first-principles calculations. Particularly, the hyperfine interactions with randomly distributed $^{13}$C nuclear spins are clearly observed to vary with temperature, and the relevant coefficients are measured with Hz-level precision. The temperature-dependent behaviors are attributed to both thermal expansion and lattice vibrations by first-principles calculations. Our results pave the way for taking nuclear spins as more stable thermometers at nanoscale. The methods developed here for high-precision measurements and first-principles calculations can be further extended to other solid-state spin defects.

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Shaoyi Xu, Mingzhe Liu, Tianyu Xie, Zhiyuan Zhao, Qian Shi, Pei Yu, Chang-Kui Duan, Fazhan Shi, Jiangfeng Du. 2022-12-06. Temperature-dependent behaviors of single spin defects in solids determined with Hz-level precision. https://arxiv.org/abs/2212.02849

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