Optical Microfiber Based Sensing Devices

Sulaiman Wadi Harun

Department of Electrical Engineering, University of Malaya

50603 Kuala Lumpur, Malaysia

Abstract— Optical microfibers are optical fibers with diameters close to the wavelength of guided light. They have attracted growing interest recently due to its interesting properties such as tight optical confinement, strong near-field interaction, and excellent mechanical strength, which offers plenty of choices for combining a variety of functionalized materials. This opens up plenty of opportunities in micro instrumentation and measurement. Here, we briefly describe the fabrication of microfiber and its structures such as loop, knot, Mach-Zehnder interferometer, coil resonator and micro-balloon using a flame brushing technique. A variety of applications of these structures are also presented. For instance, a compact inline microfiber Mach-Zehnder interferometer (MMZI) is demonstrated for high temperature sensing. The temperature sensitivity of the device was measured to be 13.4 pm/oC with an excellent linearity for temperature measurement up to 800 oC.