Opportunities for photonic integrated circuits in optical gas sensors

Abstract

In this article, the potential of photonic integrated circuits (PICs) for modern gas sensing applications is discussed. Optical detection systems can be found at the high-end of the currently available gas detectors, and PIC-based optical spectroscopic devices promise a significant reduction in size and cost. The performance of such devices is reviewed here. This discussion is not limited to one semiconductor platform, but includes several available platforms operating from the visible wavelength range up to the long wavelength infrared. The different platforms are evaluated regarding their capabilities in creating a fully integrated spectroscopic setup, including light source, interaction cell and detection unit. Advanced spectroscopy methods are assessed regarding their PIC compatibility. Based on the comparison of PICs with state-of-the-art bulk optical devices, it can be concluded that they can fill the application space of compact and low cost optical gas sensors.