GaAs Q-switched Nd:CNGG lasers: operating at 4F3/2 → 2I11/2 and 4F3/2 → 2I13/2 transitions

The nonlinear absorption properties of GaAs were measured at 1.06 and 1.34 mu m by the open aperture Z-scan technique in this paper. Based on a neodymium doped calcium niobium gallium garnet (Nd:CNGG) disordered crystal grown by the Czochralski method, passively Q-Switched lasers with the conventional GaAs wafer as the saturable absorber were demonstrated, operating on the transitions of F-4(3/2) -> I-2(11/2) and F-4(3/2) -> I-2(11/2). For the F-4(3/2) -> I-2(11/2) transition, the laser operated at 1063 nm with a pulse duration of 546 ns and a repetition rate of 98.5 kHz. While for the F-4(3/2) -> I-2(13/2) transition operating at 1340 nm, the minimum pulse width was 499.6 ns with the pulse repetition rate of 110.7 kHz. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement