Extremely High Quantum Efficiency and High Purity Rare-Earth-Doped Crystals for Solid-State Laser Cooling: Material Synthesis and Characterization
Abstract
This project concerned investigating the growth and characterization of extremely high-purity low-phonon energy crystals doped with rare-earth ions (ytterbium, thulium and holmium). The overall goals are: (1) achieving lower temperatures (approaching 70K and beyond), (2) improving efficiency, and (3) enhancing the cooling power (density). The recent record cooling studies have been obtained in high-purity Yb-doped YLiF4 (YLF) crystals. Further advances in this field should address material selection and synthesis involving (a) smaller ground state manifold splitting (Stark splitting), (b) higher doping concentration without degrading the external quantum efficiency (EQE), (c) the use of dopants with smaller energy gap such as Tm, Ho and Dy, and (d) mitigation of parasitic absorption by identifying the impurity source and purifying the starting materials. In this project, we closely collaborate with Dr. Markus Hehlen at Los Alamos National Laboratory (LANL) who is the world leading material scientist in RE-doped crystals for optical refrigeration.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 05, 2018
- Accession Number
- AD1062408
Entities
People
- Mansoor Shelk-bahae
- Markus P Hehlen
Organizations
- University of New Mexico