Raman Scattering in Single-crystal YAG for application in distributed temperature sensing

Single crystal fibers have shown great potential for harsh environment sensing applications. Interrogation schemes based on temperature dependence of Raman scattering modes in crystals, offer capability of sensing at high temperatures. Yttrium aluminum garnet (YAG) is a potential alternate to sapphire as it also has similar material properties like high melting point and chemical resistance. In this work, Raman scattering in YAG samples have been measured from room temperature to 1000 degrees C. Temperature dependence of the peak position, and peak width are measured and compared for the different peaks. A Raman based Optical time domain reflectometry (OTDR) is constructed and distributed temperature measurements of a furnace are conducted using a YAG crystal fiber.