Multifunctional nanowire evanescent wave optical sensors

A photonic sensing platform that utilizes the evanescent field of a subwavelength nanowire waveguide to perform optical spectroscopy on femtoliter probe volumes is demonstrated. Each evanescent sensor is capable of carrying out absorbance, fluorescence, and surface-enhanced Raman spectroscopy measurements on the same analyte while operating within a microfluidic flow cell (see figure).