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To overcome the main drawback of poor pump absorption of Nd : YVO4 lasers in-band pumped at 914 nm, three possible methods of higher temperature, longer crystal length and higher doping concentration were experimentally studied. A Nd : YVO4 laser operating at 914 nm was used as high beam quality, narrow line-width pump source to make the measurement of pump absorption accurate. Four different Nd : YVO4 crystals were used as gain mediums to investigate the effects of crystal parameters. We found that heating the crystal effects differently on output power and overall efficiency when crystal doping concentration changed. To improve the pump absorption and meanwhile achieve high efficiency, longer crystal with proper doping concentration and pump feedback should be adopted instead of highly doped crystal.

We report a widely tunable, narrow linewidth, pulsed Ti:sapphire laser pumped by an all-solid-state Q-switched intra-cavity frequency-doubled Nd:YAG laser. By using four dense flint glass prisms as intra-cavity dispersive elements, the output wavelength can be continuously tuned over 675–970 nm and the spectral linewidth is shortened to 0.5nm. The maximum output power of 6.65 W at 780nm is obtained under 23.4 W pump power with repetition rate of 5.5kHz; corresponding to an conversion efficiency of 28.4%. Due to the gain-switching characteristics of the Ti:sapphire laser, the output pulse duration is as short as 17.6 ns.

This work demonstrates a tunable continuous-wave (CW) all-solid-state orange-red source based on sum-frequency generation (SFG), using a tunable 1.4?1.5??m signal and a 1064?nm pump of an intra-cavity periodically poled LiNbO3 optical parametric oscillator in a BBO (?-BaB2O4) crystal. Elaborate intra-cavity design ensured efficient CW singly resonant optical parametric oscillator (SRO) operation. Intra-cavity SFG made full use of the high circulating pump and signal power of the SRO under an external laser diode (LD) pump power that was ten times higher than the SRO threshold. The output wavelength tuning range was 605?623?nm. The maximum output power was 370?mW at 622.8?nm with 17.1?W LD pump power, corresponding to an overall conversion efficiency of 2.2%.