Abstract
We present a non-contact optical technique for the measurement of laser-induced temperature changes in solids. Two-band differential luminescence thermometry (TBDLT) achieves a sensitivity of and enables a precise measurement of the net quantum efficiency of optical refrigerator materials. The TBDLT detects internal temperature changes by decoupling surface and bulk heating effects via time-resolved luminescence spectroscopy. Several -doped fluorozirconate (, ZBLANI) glasses fabricated from precursors of varying purity and by different processes are analyzed in detail. A net quantum efficiency of at 238 K (at a pump wavelength of 1020.5 nm) is found for a ZBLANI:1% laser-cooling sample produced from metal fluoride precursors that were purified by chelate-assisted solvent extraction and dried in hydrofluoric gas. In comparison, a ZBLANI:1% sample produced from commercial-grade metal fluoride precursors showed pronounced laser-induced heating that is indicative of a substantially higher impurity concentration. The TBDLT enables rapid and sensitive benchmarking of laser-cooling materials and provides critical feedback to the development and optimization of high-performance optical cryocooler materials.
© 2010 Optical Society of America
Full Article | PDF ArticleMore Like This
Galina Nemova and Raman Kashyap
J. Opt. Soc. Am. B 27(12) 2460-2464 (2010)
Denis V. Seletskiy, Markus P. Hehlen, Richard I. Epstein, and Mansoor Sheik-Bahae
Adv. Opt. Photon. 4(1) 78-107 (2012)
C. W. Hoyt, M. P. Hasselbeck, M. Sheik-Bahae, R. I. Epstein, S. Greenfield, J. Thiede, J. Distel, and J. Valencia
J. Opt. Soc. Am. B 20(5) 1066-1074 (2003)