Photon Avalanche Upconversion in Er(3+):YA10 sub 3

摘要

The results of an investigation of photon avalanche upconversion pumping inEr3+:YA10sub 3 are reported. Five pump wavelengths corresponding 10 transitions from the metastable 4I13/2 state to the 2H11/2 state generated upconversion laser emission at 549.8 nm. The dependence of the laser output power on pump power near laser threshold is discussed in terms of a four-level kinetics model and is shown to reflect thc threshold power requirement for photon avalanche. The maximum output power at 7K was 33 mW, giving an optical conversion efficiency of 3.5% and a conversion efficiency of 28% based on absorbed power. Pumping Fr:YALO by cross relaxation energy transfer produced 166 mW of laser output with an optical conversion efficiency of 17%. (MM).