Chromium doped phosphor based fiber-optic thermometer

Abstract

A variety of chromium (Cr/sup 3+/) doped phosphors has been studied for a sensor head materials in the fiber-optic thermometer, have been studied. Cr doped alumina (Cr:Al/sub 2/O/sub 3/), spinel (Cr:MgAl/sub 2/O/sub 4/) and yttrium ortho-aluminate (Cr:YAlO/sub 3/) crystals are grown using floating zone (FZ) technique. The value and temperature coefficient of photoluminescence (PL) lifetime are evaluated using the fiberoptic thermometer equipment. The value and temperature coefficient of PL lifetime vary greatly with the host materials. Among them, perovskite type Cr:YAlO/sub 3/ crystal shows the longest PL lifetime and the largest temperature coefficient. Cr doped YAlO/sub 3/ crystal is a potentially useful sensor material for fiber-optic thermometer due to long PL lifetime and large temperature coefficient of PL lifetime.