Temperature Sensing With Nd3+ Doped Yas Laser Microresonators

Featured ApplicationThe investigated YAS glass microspheres doped with Nd3+ ions have great potential as remote optical temperature sensors. Moreover, they are suitable for the development of laser devices with low power thresholds.Yttria-alumina-silica (YAS) glass microspheres doped with Nd3+ ions were excited with a 532 nm continuous laser in order to study the dependency of the wavelength of the whispering gallery mode (WGM) peaks on the temperature of the sample. This was possible due to a previous calibration of the 808 nm and 890 nm emission bands of the Nd:YAS glass sample for different temperatures using the fluorescence intensity ratio (FIR) technique. A maximum sensitivity of 15 x 10(-6) K-1 and a temperature resolution limit of 0.2 K were obtained for the microsphere sensor. Moreover, laser emission at 1064 nm was observed by continuous pumping at 532 nm, and a power threshold of 100 mW was determined. Upconversion emissions of Nd3+ were also studied by exciting the sample at 808 nm.