Multi-channel sensing with resonant microcavities coupled to a photonic crystal waveguide

We report on multiple resonant cavities coupled to a single photonic crystal waveguide operating as a multi-channel sensor. This device is characterized by as many dips in its transmission spectrum as there are cavities. Good reproducibility is observed between the spectrum of double-channel device and those of the single cavities. Infiltration of isopropanol in the holes leads to a red shift of the resonance wavelengths.