Ultrahigh Sensitive Temperature Sensor Based on Fabry–Pérot Interference Assisted by a Graphene Diaphragm

A miniature Fabry-Pérot interferometer is proposed and experimentally demonstrated for temperature measurement. The cavity of the interferometer is a small air gap between the end-face of a single-mode fiber and an ultrathin graphene. A well-defined interference spectrum is obtained, and the dip wavelengths are employed to demonstrate the temperature change. Due to the smart intrinsic characteristics of the graphene film, the proposed device can measure the temperature up to 1008°C, and shows an ultrahigh sensitivity of 1.56 and 1.87 nm/°C at the temperature range of 500°C-510°C and 1000°C-1008°C, respectively, making it a good candidate for high-temperature monitoring in the harsh environment.