Non-collinear phase-matching method for stimulated polariton scattering based on cross-pumping

The method for achieving non-collinear phase matching in stimulated polariton scattering (SPS) using cross-pumping is proposed. Under sub-nanosecond pulse laser pumping conditions, tunable narrowband Stokes light output is obtained. The cross-pumping configuration is established by total internal reflection of the pump light on the side of the crystal. By rotating the crystal, altering the total internal reflection angle of the pump light, thereby changing the phase matching condition and tuning the frequency of the output Stokes light. The output Stokes light is with a linewidth of 0.2 nm. The wavelength tuning range is 1068 nm to 1075 nm. At a pump energy of 8 mJ, the output energy is 1.1 mJ, corresponding to a conversion efficiency of 13.8%. This study provides a reference for phase matching methods in nonlinear parametric conversion processes.