Measurement of Solid-state Optical Refrigeration by Two-band Differential Luminescence Thermometry
Author | : |
Publisher | : |
Total Pages | : |
Release | : 2009 |
ISBN-10 | : OCLC:727237434 |
ISBN-13 | : |
Rating | : 4/5 ( Downloads) |
Download or read book Measurement of Solid-state Optical Refrigeration by Two-band Differential Luminescence Thermometry written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a non-contact spectroscopic teclmique for the measurement of laser-induced temperature changes in solids. Two-band differential luminescence thermometry (TBDLT) achieves a sensitivity of ≈7 mK and enables precise measurement of the net quantum efficiency of optical refrigerator materials. TBDLT detects internal temperature changes by decoupling surface and bulk heating effects via time-resolved luminescence spectroscopy. Several Yb{sup 3+}-doped fluorozirconate (ZBLANI) glasses fabricated from precursors of varying purity and by different processes are analyzed in detail. A net quantum efficiency of 97.39% at 238 K (at a pump wavelength of 1020.5 nm) is found for a ZBLANI:1%Yb{sup 3+} 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%Yb{sup 3+} sample produced from commercial-grade metal fluoride precursors showed pronounced laser-induced heating that is indicative of a substantially higher impurity concentration. 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.