High-speed colour-converting photodetector with all-inorganic CsPbBr perovskite nanocrystals for ultraviolet light communication.

Optical wireless communication (OWC) using the ultra-broad spectrum of the visible-to-ultraviolet (UV) wavelength region remains a vital field of research for mitigating the saturated bandwidth of radio-frequency (RF) communication. However, the lack of an efficient UV photodetection methodology hinders the development of UV-based communication. The key technological impediment is related to the low UV-photon absorption in existing silicon photodetectors, which offer low-cost and mature platforms.

375-nm ultraviolet-laser based non-line-of-sight underwater optical communication.

For circumventing the alignment requirement of line-of-sight (LOS) underwater wireless optical communication (UWOC), we demonstrated a non-line-of-sight (NLOS) UWOC link adequately enhanced using ultraviolet (UV) 375-nm laser. Path loss was chosen as a figure-of-merit for link performance in this investigation, which considers the effects of geometries, water turbidity, and transmission wavelength. The experiments suggest that path loss decreases with smaller azimuth angles, higher water turbidity, and shorter wavelength due in part to enhanced scattering utilizing 375-nm radiation.