551 nm Diode-Laser-Pumped Upconversion Laser

Green laser emission at 551 nm was achieved in LiYF4: Er3+ by upconversion pumping with a near-infra-red diode laser at low temperature. Using a 2mm-long monolithic laser crystal the lasing threshold was reached with 34 mW of absorbed power from an AlGaAs diode-laser array. © 1989, The Institution of Electrical Engineers. All rights reserved.