In this letter a humidity and pressure PMMA capillary Whispering-Gallery Resonator sensors are developed. The excitation of the WGMs is performed evanescently with a fiber taper. The experimental results show a sensitivity of 0.07 nm/% RH for the humidity sensor and a sensitivity of 0.36 nm/bar for pressure sensor. Hysteresis has been noticed in the humidity one as result of the PMMA water absorbance. Theoretical models that explain both sensors are introduced and show good agreement with the collected data.
© 2014 Optical Society of AmericaPDF Article