Nanoparticle Sensing Utilizing Back Scattering Reflection Mode of an Integrated Micro-Resonator

We have demonstrated an optical sensing device based on back scattering signal changes in the transfer functions of an integrated silicon-based optical resonator, which are induced by the presence of one or more nanoparticles in the resonator's evanescent field. The nanoparticles may be used as taggants to label other species to be detected. Our work offers several potential advantages to optical sensing, including improved detection limits, relaxed resonator fabrication requirements, CMOS compatibility and the use of simpler, lower cost optical sources and detectors.