Kinetics of Er3+ emission under laser-thermal excitation of Er2O3

Kinetics of emission of Er³⁺ ions in Er₂O₃ polycrystals in visible and NIR ranges was investigated under excitation by ~30 s and 300 ns pulses of intensive CO₂ laser radiation at wavelength λ = 10.6 μm. A delay time of Er³⁺ emission pulses relative laser pulses of ~1.5 μs comparable with multiphonon relaxation time of 4I13/2 states was detected and explained as the time of multiphonon excitation of the states. The delay effect is confirmed by comparison of experimental and calculated kinetics of Er₂O₃ emission and looks to be a base of laser-thermal method of measurement of multiphonon excitation times of vibronic states of ions in rare-earth oxides.