Energy scaling of a narrow-band PPLN non-resonant optical parametric oscillator

We demonstrate that thick (3-mm) Periodically-Poled LiNbO3 (PPLN) enables energy scaling of a non-resonant optical parametric oscillator (NRO) operated in the narrowband mode with a Volume Bragg grating (VBG) at the signal wavelength. Utilizing the full available pump power at 1064 nm we obtained maximum average powers of 2.25 and 2.08 W for the signal (1822 nm) and idler (2383 nm) at 10 kHz, at a conversion efficiency of 32.8%, i.e. a two-fold increase in terms of pulse energies. The signal and idler linewidths were ⁓1 nm, the pulse lengths ⁓6 ns and the idler beam propagation factor ⁓5.