▎ 摘　　要

This paper proposes a novel Ultraviolet (UV) sensor in a Mach-Zehnder Interference (MZI) structure consisting of a coupler and a microfiber coupler (MFC) coated with zinc oxide (ZnO) and ZnO composite graphene. Since the MFC is highly sensitive to the surrounding refractive index (RI), and the RI of ZnO is sensitive to UV light, the UV sensing function of this structure is realized. ZnO and ZnO composite graphene materials were prepared by hydrothermal method and coated on the surface of MFC as a thin layer. The effects of various shapes of ZnO and its composites on the sensitivity of UV sensors were investigated. The experimental results show that the higher sensitivity of the sensor for ultraviolet sensing ranging from 4.6310 nW/cm(2) to 7.1995 nW/cm(2) can reach 2443.7 pm/nW center dot cm(-2) with the flake ZnO composite graphene. The MFC-MZI structure combined with UV sensitive materials provides a simplified platform for UV detection technology with potential applications in partial discharge, open fire detection, and solar illumination monitoring.