All-polymer whispering gallery mode resonators for gas sensing

Sensitivity of polymeric microdisks is evaluated for selected compounds in their vapor phase such as humidity, isopropanol, toluene, limonene, 1-butanol, and pentanoic acid (valeric acid). Among these compounds, exhibits the highest sensitivity (23 pm/ppm) with a limit detection estimated to be around 0.6 ppm. We are interested contribution geometry deformation due polymer swelling on it may engineered improve performance gas sensing devices. Experimental observations show trend where humidity increased ratio undercut over radius microcavity.