Microstructure Engineering of Hexagonal Boron Nitride for Single-Photon Emitter Applications

Single-photon emitters (SPEs) can play an important role in future quantum optics. Hexagonal boron nitride (h-BN), a layered insulator (bandgap approximate to 6 eV), is a promising candidate for next-generation SPEs because of its chemical and thermal stability and high brightness at room temperature. In this review, the microstructures (atomic defects, deformations, and cavities) of h-BN are established and their SPE characteristics are analyzed. Recent progress in the synthesis of high-quality bulk h-BN, monoisotopic h-BN, and epitaxial h-BN films is also demonstrated. Some approaches for achieving SPE arrays are further discussed and the applications of h-BN SPEs in the quantum field are investigated. The success in the preparation of large-scale h-BN and its microstructural engineering provides a promising future in low-dimensional quantum optics.