Abstract Vibrational spectroscopy, due to its inherent specificity in providing a spectral “fingerprint” of molecular composition, is an important tool to identify and quantify molecules in environmental, clinical, biotechnological, security, and manufacturing process applications, for example. Optical waveguide chips, offering mass production, robustness, sensitivity and the potential for widespread, low-cost deployment as sensors, are being exploited in two principal forms of vibrational spect