Thermally induced red-shift of whispering gallery modes of microspheres in Er:ZBLALiP

In this paper, we experimentally observe thermally induced red-shift of whispering gallery modes spectrum in microspheres based on erbium-doped heavy-metal fluoride glass (Er:ZBLALiP). Also we propose a new optical temperature sensor using micrometer-sized spherical cavity composed of erbium doped fluoride glass.