Pump wavelengths for an Er:YLiF4 green-emitting laser

Abstract We investigate the emission regimes of a room-temperature Er(1%):YLiF 4 laser on the transition 4 S 3/2 → 4 I 15/2 using a model based on rate equations. The influence of the excited-state reabsorption losses and of the pump wavelength on the laser emission regime is discussed. Three pump wavelengths are investigated: 486 nm (direct pumping), 795 nm and 810 nm (both corresponding to upconversion pumping). The emission thresholds of the various regimes are determined.