2CaO·Al2O3:Er3+ glass: An efficient optical temperature sensor.

An Er 3+ -doped calcium aluminate glass has been studied in order to establish its suitability as optical temperature sensor based on the fluorescence intensity ratio technique. Temperature-induced changes in the relative intensities of the green emissions associated with the transitions from the 2 H 11/2 and 4 S 3/2 thermalized levels to the 4 I 15/2 ground state under laser excitation at 488 nm has been measured in the range of temperatures from 150 to 762 K. The sensitivity obtained due to temperature changes shows a maximum of 159×10 −4 K −1 at 645 K, one of the highest sensitivity values found in Er 3+ -doped host matrices. Compared to other studies, a different approach has been followed to estimate the calibration the temperature sensor using a low-cost prototype. [ABSTRACT FROM AUTHOR]