Weidong Chen

Yellow-light generation of 5.7 W by intracavity doubling self-Raman laser of YVO 4 /Nd:YVO 4 composite

A high-power 588 nm light produced by an intracavity frequency-doubling acousto-optic Q-switched self-frequency Raman laser is reported. A 20-mm-long YVO(4)/Nd:YVO(4) composite crystal and a 15-mm-long LiB(3)O(5) (LBO) with noncritical phase-matching (theta=90 degrees , phi=0 degrees ) cut were adopted for efficient self-Raman laser operation and second-harmonic generation, respectively. By the optimizing the focus position of incident pump light and Q-switch repetition rate, yellow light with 5.7 W average power was generated under the pump power of 23.5 W, corresponding to the overall diode-yellow conversion efficiency of 24.2% and slope efficiency of 32%. The pulse width is about 16 ns, and the pulse energy is up to 95 microJ.

Second-Stokes YVO 4 /Nd:YVO 4 /YVO 4 self-frequency Raman laser

We demonstrated an efficient second-Stokes Raman laser emission at 1313 nm based on self-frequency stimulated Raman scattering from a diode-end-pumped actively Q-switched YVO(4)/Nd:YVO(4)/YVO(4) laser at 1064 nm for the first time, to the authors knowledge. A double-end diffusion-bonded Nd:YVO(4) composite crystal was adopted for sufficiently improving the thermal lensing effect in the course of self-frequency stimulated Raman scattering operation. With an incident pump power of 14.6 W and a pulse repetition (PRR) of 40 kHz, a maximum average output power of 2.34 W was obtained, corresponding to an optical-to-optical conversion efficiency of 16%. Pulse width and peak power were 1.2 ns and 49 kW, respectively.

Achievement of an efficient 1053 nm Nd:YLF polarized laser based on different thermal lensing effects

The negative and positive thermal focal lengths for 1047xa0nm and 1053xa0nm were respectively demonstrated through analyzing different thermal lensing effects along the π- and σ-polarizations in a plane-parallel resonator. A compact and efficient diode-end-pumped 1053xa0nm Nd:YLF polarized laser is presented. As high as 11.2xa0W output power of the polarized 1053xa0nm laser has been obtained at an absorbed pump power of 22.3xa0W with an optical–optical efficiency of 50% and a slope efficiency of 53%. With the aid of a ray propagation matrix and a λ/4 wave plate, different thermal lensing effects for the π- and σ-polarizations have been theoretically analyzed and experimentally verified.

Spectra and broad-spectral laser operation of a disordered Nd:LiLa(MoO4)2 crystal

The crystal characteristics of a disordered Nd:LiLa(MoO4)2 laser crystal were investigated in detail, including its structure, absorption, emission and Raman scattering spectra. Laser operation, end-pumped by an 808u2009nm diode laser, has been demonstrated in both a concave-plano and plane-parallel resonator cavity. A broad-spectral dual-peak laser emission at 1061u2009nm and 1060u2009nm with a full width at half maximum of 2u2009nm was obtained in the experiment. A maximum output power of 267u2009mW was obtained in the concave-plano cavity. However, in the plane-parallel cavity, laser output of 381u2009mW was obtained, giving a slope efficiency of 14.5%. The results lay the groundwork for Raman, mode-locked and tunable laser applications generated by a Nd:LiLa(MoO4)2 laser crystal.

Efficient end-pumped multi-wavelength laser operation of disordered Nd:LiGd(WO4)2 crystal

An efficient laser operation of disordered Nd:LiGd(WO4)2 laser crystal, end-pumped by a quasi-CW 808 nm diode laser, has been demonstrated in both free-running and actively Q-switched modes. Multi-wavelength emission around 1.06 μm was obtained simultaneously in this paper. In free-running status, 0.63 W laser output was obtained, giving a slope efficiency of 40.6%. When the repetition rate was 40 kHz in Q-switched operation, a maximum average output power of 0.43 W and a slope efficiency of 30.2% were obtained. This work indicated that Nd:LiGd(WO4)2 could be a promising laser crystal for THz, mode-locked and tunable laser applications.