Temperature Sensor Based on Microbottle Resonator Immersed in Isopropanol

Temperature measurement of an isopropanol-immersed microbottle resonator is demonstrated. The theoretical analysis indicates that the resonance wavelength blue shifts as the increase of temperature, and the temperature sensitivity increases with the decrease of resonator dimension, which are also demonstrated by experimental results. The temperature sensitivity enhancement of up to 4.6 times relative to the sensor in the air is achieved, which could be benefit from the high thermal refraction coefficient of isopropanol. Furthermore, a robust package has also been proposed to make the present sensor more practically.