[8p-Z13-11~16] 12.3 Functional Materials and Novel Devices

[8p-Z13-11] On-substrate Microdroplet Optical Resonator as Precise Temperature Sensor

〇(M1)Keitaro Fujita¹, Hiroshi Yamagishi¹, Yohei Yamamoto¹ (1.Grad. Sch. Pure Appl. Sci., Univ. Tsukuba)

Keywords:optical resonator, temperature sensor, Whispering Gallery Mode

Here, we show a high-precision temperature sensor based on a spherical microdroplet optical resonator. The droplet is doped with an organic dye and put on a super hydrophobic substrate to form a spherical shape. Heating and cooling of the substrate induce reversible blue- and red-shift of the WGM resonant peaks, respectively. The temperature sensitivity of the droplet measured in a range from 20 to 35 °C is 2.40 nm/°C, which is much higher than the reported solid optical microresonators. The blue- and red-shift of the WGM peaks upon heating and cooling are respectively attributed to the contraction and expansion of the droplet. The droplet deforms slightly, which leads to a noticeable shift of its resonance peaks.