Abstract

Optical biosensors provide high sensitivity and label-free operation with applications ranging from clinical diagnostics to a better understanding of biomolecular dynamics [1]. In the field of integrated photonic crystal biosensors [2], guided-mode resonance (GMR) gratings [3] are particularly powerful due to their advantage of providing out-of-plane excitation and resonant imaging [6] in addition to high quality resonances and high extinction ratios. The current limitations of GMR based biosensing are given by light source intensity noise and the spectral resolution of spectrometers and monochromators. To overcome these limitations, we propose a novel interferometric approach with on-chip reference beam and simple interferogram read-out to probe the phase change introduced by biomolecular binding on the sensor surface.

© 2019 IEEE