Room-temperature 1.532-μm pumped 1.645-μm laser action in the Er3+:Y3Al5O12(Er:YAG) 4I13/2y3 (6602-cm−1) ⇒ 4I15/2z7 (523-cm−1) transition was demonstrated and was analyzed. Laser action at 1.645 μm was achieved in Er:YAG crystals with Er concentrations ranging from 0.5% to 4%. Slope efficiencies as high as 40% were obtained with 0.5% Er:YAG. For concentrations up to 4%, measurements of laser thresholds indicate that upconversion losses were small.
© 1994 Optical Society of America
Kalin Spariosu, Milton Birnbaum, and Bruno Viana, "Er3+:Y3Al5O12 laser dynamics: effects of upconversion," J. Opt. Soc. Am. B 11, 894-900 (1994)