Fiber-laser-pumped, dual-wavelength, picosecond optical parametric oscillator.

Abstract

We report a simple, compact, picosecond, dual-wavelength optical parametric oscillator (DW-OPO) at 160 MHz, based on two MgO:PPLN crystals sharing the same cavity and synchronously pumped by an Yb-fiber laser at 1064 nm. The two signal and idler wavelength pairs are independently tunable in the near- and mid-infrared across 1550-1615 nm and 3118-3393 nm, respectively, and can be arbitrarily tuned, even to degeneracy and beyond, without coherent coupling, irrespective of operating wavelength. The DW-OPO provides two signal and idler pulse trains and delivers as much as 1.5 W of average signal power at a degenerate wavelength of 1550 nm from each arm, at a total (signal plus idler) power extraction efficiency of as much as 44%. The two output signal pulse trains have durations of ∼18 ps and ∼15.2 ps, with Gaussian spatial quality, and exhibit passive power stability, better than 3.6% rms over >5 h. We also demonstrate the possibility of tailoring the pulse trains from the DW-OPO by controlling the delay between the pump pulses at the input to the two MgO:PPLN crystals.