Liquid core modal interferometer integrated with silica waveguides

• Published in: IEEE photonics technology letters Vol. 18; no. 6; pp. 746 - 748
• Main Authors: Dumais, P., Callender, C.L., Noad, J.P., Ledderhof, C.J.
• Format: Journal Article
• Language: English
• Published: New York IEEE 15.03.2006; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Integrated optics; Liquid waveguides; Liquids; Microchannel; Microchannels; Microsensors; Optical data processing; Optical interferometry; optical planar waveguide components; Optical refraction; Optical sensors; optical transducers; Optical variables control; Optical waveguides; Refractive index; Refractivity; Silica glass; Silicon compounds; Silicon dioxide; Waveguides
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2006.871109

An integrated structure is demonstrated as a refractive index sensor. The structure consists of a liquid-filled elliptical microchannel embedded in silica glass and integrated with waveguides. The microchannel features entry points that are open to the top surface of the device and distinct from the optical input. The structure allows light to couple from a solid-core input waveguide to the liquid-core waveguide formed by the microchannel, and back to a solid-core output waveguide. Bimodal interference allows the structure to be sensitive to the refractive index of the liquid, with a full beat corresponding to a refractive index change of /spl sim/10/sup -4/. The structure allows the direct integration of optical fluids with silica waveguides for sensing and optical processing applications.