Thermo-Sensor Based on Peak Intensity Ratio of Photoluminescence from Cr Doped YAG Crystals

Temperature dependence of peak intensity and peak intensity ratio of photoluminescence (PL) from garnet crystal sensor is evaluated for fluorescence thermometer application. Peak intensity of PL from YAG sensor decreases exponentially with temperature. Intensity ratio of PL peaks at 690nm, 688nm and 688nm, I
₆₇₈
/I
₆₈₉
, I
₇₀₇
/I
₆₈₉
, I
₇₂₅
/I
₆₈₉
, increases linearly with temperature from 299 to 473K. Cr doped YAG is potentially useful sensor material in fluorescence thermometer based on temperature dependences of PL intensity, and PL intensity ratio