A High Sensitivity Ethanol Sensor Based on Photo-imprinted, Micro-ring Resonators on Optical-Fiber Tapers

The detection of vapours of organic solvents at low concentrations impacts significant market sectors such those of chemical processing, safety, and security. The interaction of organic molecules in the gas phase with optical surfaces mostly refers to physisorption processes, with typical adhesion monolayers in the scale few nm’s or lower; the transduction mechanism for tracing those vapours using evanescent field interactions is a significant challenge. Few gas sensing probes have been realised using planar micro-ring resonators (MRRs), while being used for detecting inert gas pressure changes or vapours of organic molecules using oxide layers.