Micro-photoluminescence imaging of hexagonal boron nitride crystal in the UV range

Since the synthesis of a single macro crystal of hexagonal boron nitride ( h-BN) under high pressure high temperature conditions by Watanabe et al. in 2004 [1], h-BN has become an extensively studied material. Nonetheless, numerous questions about its photoluminescence properties still remain unanswered. h-BN being a key compound in the technology of devices based on 2D crystals along with the transition metal dichalcogenides (TMDC), and as a viable candidate for hosting single photon emitters operating in the UV range, efforts to investigate these pending questions are done. Even though evidence of single photon emitters in UV spectral range has already been reported by using cathodoluminesence techniques [2], neither systematic measurements of the photophysics in these defects have been performed nor clear understanding of chemical origins have been brought to the scientific community's attention for now.