Ultra Sensitive Bio-Chemical Sensors Based on Optical Resonance

摘要

With the focus on bio terrorism and environmental sensing, there is need for development of smart integrated bio-chemical sensors. We investigate Whispering Gallery Mode (WGM) based High Q micro cavity as a biosensor. We integrate the lab-on-a-chip approach with High Q technology to develop highly selective and smart sensors for in-situ detection of aqueous media based agents. We have investigated the ring based micro-cavity structure as a sensor. We identify the detection of agent through the changes observed in the wavelength shift and Q factor as a result of enzyme-substrate interactions. We report an experimental demonstration of a compact micro-cavity based biochemical sensor based on the micro ring structure. The micro-cavity, fabricated on a silica-on-silicon substrate, is designed to have a resonant wavelength (1) near 1.34 μm. The transmission spectrum of the sensor is measured with different ambient refractive indices ranging from n =1.0 to 1.5. Chemical detection was achieved by measuring the shift in resonant wavelength, and variation to the quality factor