Widely tunable second harmonic amplification by noncollinear phase matching in bulk birefringent materials

摘要

Second harmonic amplification - a hybridization of optical parametric amplification and second harmonic generation - is a route to ultra-efficient parametric amplification. Requiring the simultaneous phase matching of two parametric wave-mixing processes, it has limited frequency coverage in the collinear geometry in bulk media. Here we show that noncollinear birefringent phase matching can provide wide frequency tunability of second harmonic amplification across the near- and mid-infrared in the materials ZnGeP_2, CdSiP_2, LiNbO_3, β- BaB_2O_4, and KD_2PO_4 in applications designed for accommodating high-energy picosecond pulses generated by solid state lasers. We discuss practical limitations including acceptance angle, phase-matching bandwidth, spatial walk off, and parasitic processes.