Frequency down-conversion of a dual-wavelength fiber laser

The experimental study of frequency down-conversion processof a dual-wavelength fiber laser by using an MgO:PPLN nonlinear crystal was presented. The dual-wavelength fiber laser was a home-made linearly polarized fiber laser with a maximal output power of 74.1 W at 1060 nm and 1080 nm. A total idler output power of 6.36 W with dual idler-waves at 3125 nm and 3323 nm was obtained. The corresponding pump-to-idler slope efficiency was 11.4%. In the experiment, only one signal wavelength of 1603 nm was observed, which indicated that only one optical parametric oscillation occurred while the other pump laser was contributed to the intra-cavity difference frequency generation (DFG) process. This work provides an effective approach to generate dual-wavelength mid-infrared (MIR) lasers for its features of convenience and controllability.