1.8-μm MgO: PPLN optical parametric oscillator pumped by Nd: YVO4/YVO4 2nd-Stokes Raman laser

An efficient MgO: PPLN singly resonant optical parametric oscillator (SROPO) pumped by a Nd: YVO4/YVO4 2nd-Stokes Raman laser at 1313 nm was demonstrated. The maximum conversion efficiency of 54.8% was obtained at the pump power of 1.16 W, which was higher than that of the OPO pumped by 1st-Stokes Raman laser at 1176 nm, due to the better beam quality, narrower line width and pulse width of the 2nd-Stokes Raman laser. The maximum output power of 1.57 W at 1855.5 nm with the pulse repetition frequency (PRF) of 40 kHz was achieved under the pump power of 4 W. The corresponding conversion efficiency was 39.7%, with the pulse width of 2.53 ns, linewidth of 0.45 nm, and M-2 of 1.87. Meanwhile, with the crystal period ranging from 27.91 to 29.98 mu m, the tuning range of signal wave was 1778.6-1861.8 nm.

Automated summary

The study demonstrated an efficient MgO:PPLN singly resonant optical parametric oscillator pumped by a Nd:YVO4/YVO4 laser, achieving high conversion efficiency and output power with excellent optical performance. The tuning range of the signal wave can be achieved by adjusting the crystal period.