An integrated photonic sensor for in situ monitoring of hazardous organics

This study discusses the design, fabrication, and performance of an integrated photonic sensor based on the principles of single mode Mach-Zehnder interferometry. The sensor consists of a patterned waveguide structure consisting of a lower silica clad, a phosphosilicate core and an upper borophosphosilicate clad. Results indicate that such a sensor is sensitive to refractive index changes caused by the presence of small concentration of organics in water over the wavelength range of 1.25–1.65 μm.