Infrared laser generation by cascaded difference frequency generation combined with optical parametric oscillator

We introduce an infrared laser generation scheme by cascaded difference frequency generation (CDFG) combined with optical parametric oscillator (OPO). An inventive infrared laser generator is proposed that enable cascaded optical waves, initially generated by CDFG in an aperiodically poled lithium niobate crystal, then continuously and repeatedly transferred to high-order Stokes waves by oscillations of cascaded optical waves, and finally brought out infrared laser from the high-order Stokes waves with specially designed OPO. We explain the physical mechanism of the above infrared laser generation process and demonstrate wide frequency tuning characteristics and high conversion efficiency characteristics of the infrared laser generator by providing theoretical research. The frequency tuning from pump frequency to 60 THz with a high conversion efficiency are realized by numerical calculations. The infrared laser generator exhibits physics distinctly different from lasers by atomic transitions, optical parametric oscillation or difference frequency generation. We consider that the infrared laser generator based on CDFG combined with OPO is promising for achieving high-efficiency and high-power infrared laser.