分类: 光学 >> 量子光学 提交时间: 2023-02-19
摘要: Optically addressable spin defects in solid-state materials are the promising platform for quantum information applications, such as quantum network. The two-dimensional (2D) hexagonal boron nitride (hBN) as a carrier of abundant defects is an emerging candidate. While negatively charged boron vacancy (V$_\text{B}^-$) spin defect in hBN is studied intensively, the coherent control of single spin in 2D materials has not been realized yet, which constitutes the cornerstone for applying the 2D spin defect in quantum-information tasks. Here, we report the first coherent control of the single electronic spin in 2D materials at room temperature. Considering both the optical and spin properties, this defect belongs to a new type of spin defects distinguished to all other spin defects observed before. This defect has simultaneously the narrow zero-phonon line, high Debye-Waller factor, high brightness, high polarization of PL photons, low $ g^{(2)}(0) $, moderate spin $ T_{1} $ and $ T_{2} $ comparable to V$ _\text{B}^{-} $. These excellent optical properties and relatively good spin properties of this single spin lay the foundation for the applications of the 2D-material-hosted spin defects in quantum information tasks.
分类: 光学 >> 量子光学 提交时间: 2023-02-19
摘要: Optically addressable spins in two-dimensional hexagonal boron nitride (hBN) attract widespread attention for their potential advantage in on-chip quantum devices, such as quantum sensors and quantum network. A variety of spin defects have been found in hBN, but no convenient and deterministic generation methods have been reported for other defects except negatively charged boron vacancy ($\rm V_B^-$). Here we report that by using femtosecond laser direct writing technology, we can deterministically create spin defect ensembles with spectra range from 550 nm to 800 nm. Positive single-peak optically detected magnetic resonance (ODMR) signals are detected in the presence of longitudinal magnetic field, and the contrast can reach 0.8%. With the appropriate thickness of hBN flakes and femtosecond laser pulse energy, we can deterministically generate bright spin defects in-situ. Our results provide a convenient deterministic method to create spin defects in hBN, which will motivate more endeavors for future researches and applications of spin-based technologies.