Laser Direct Writing of Visible Spin Defects in Hexagonal Boron Nitride for Applications in Spin-Based Technologies

Abstract

Optically addressable spins in two-dimensional hexagonal boron nitride (hBN) attract widespread attention for their potential advantages in on-chip quantum devices, such as quantum sensors and quantum networks. A variety of spin defects have been found in hBN, but no convenient and deterministic generation methods have been reported for other defects except the negatively charged boron vacancy (V ) B . Here we report that by using femtosecond laser direct writing technology, we can deterministically create spin defect ensembles with spectral range from 550 to 800 nm on nanoscale hBN flakes. Positive single-peak optically detected magnetic resonance (ODMR) signals are detected in the presence of a magnetic field perpendicular to the substrate, and the contrast can reach 0.8%. With the appropriate thickness of hBN flakes, substrate, and femtosecond laser pulse energy, we can deterministically and efficiently generate a bright spin defect array. Our results provide a convenient deterministic method to create spin defects in hBN, which will motivate more endeavors for future research and applications of spin-based technologies such as a quantum magnetometer array.

Color Centers in Hexagonal Boron Nitride

“…The spin texture of these carbon color centers is also under investigation for making use of them for quantum memory. Carbon-based color center defects in hBN are being actively studied as single-photon emitter platforms for quantum information; in particular, the stable emission of an ultraviolet photon from the 6C color center is gathering the most attention ([ 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 ]).…”

Single-Photon Emission from Point Defects in Hexagonal Boron Nitride Induced by Plasma Treatment

“…Despite their ubiquity, these emitters are often spatially random, characterized by low density and nonuniform optical properties . To address these issues, various postprocessing methods, including ion/electron irradiation, , focused ion beam (FIB) treatment, ,, plasma treatment, − femtosecond laser ablation, , and atomic force microscopy (AFM) tips nanoindenting, have been adopted to create high-density quantum emitters. These approaches yield emitters with similar spatial distributions or uniform optical properties.…”

Reflective dielectric cavity enhanced emission from hexagonal boron nitride spin defect arrays

“…12 Recent studies have shown the existence of color centers in hBN capable of spin initialization, readout, and coherent manipulation at room temperature. [13][14][15][16][17][18][19][20] The negatively charged boron vacancy (V B…”