INFRARED QUANTUM COUNTER ACTION IN Ho-DOPED CRYSTALS

Abstract
Infrared quantum counter action of Ho3+ in CaWO4, SrWO4, NaLa(WO4)2, CaMoO4, CdF2, and YAG single crystals is reported for the first time. A new two‐step excitation is also reported for Ho3+ in CaF2. Total quantum efficiencies were experimentally calculated for some of the stronger processes, and one of these is compared to a theoretical estimate for the internal quantum efficiency.