A Temperature Sensor Based on the Graphene-Oxide-Coated Micro-Nano-Fiber Mach–Zehnder Interference Structure

We propose a temperature sensor based on the graphene-oxide-coated micro-nano-fiber Mach–Zehnder (MZ) interference structure. In the design of the sensor, we use a single-mode fiber and multimode welded micro-nano fiber as a substrate to deposit graphene oxide (GO) by natural deposition. We cover the surface of the micro-nano fiber by a temperature-sensitive material in order to increase the temperature sensitivity of the sensor. We design a temperature sensing experimental system. The experimental results show that the temperature change can significantly change the GO influence on the transmitted light field, so that the light signal passing through the sensor is red-shifted. When the temperature increases from 25°C to 75°C, the output interference signal has a drift of 1.15 nm, and the temperature sensitivity of the sensor is 23.7 pm/°C.