An Ultrasensitive Temperature Sensor in 1550 nm Communication Band Based on MoO2 Coated Microstructured Optical Fiber

In this paper, the 2D material MoO2 is innovatively chosen to replace traditional precious metals such as Au and Ag as the plasmonically excited material, and for the first time, it is combined with the extreme thermal optical material polydimethylsiloxane (PDMS). A D-type microstructured fiber is used as the optical information transmission medium and open sensing channel, and a surface plasmon resonance (SPR) effect based MOO2 coated D-type microstructured fiber temperature sensor is constructed. The simulation results show that the temperature detection range of the proposed optical fiber sensor is 30 degrees C similar to 80 degrees C, and the sensing range of resonance wavelength is near the communication band of 1550 nm. The sensor is very sensitive to temperature variations, in particular the average wavelength sensitivity is up to 9.217 nm/degrees C in the x-polarized direction and 9.443 nm/degrees C in the y-polarized direction. This means that the sensor can accurately measure small changes in ambient temperature and respond quickly to ensure stable system operation. Therefore, MoO2 as a plasmonic sensing material and PDMS as a temperature sensing material have great potential for fiber sensing applications.