Third harmonic generation based on Stark-chirped rapid adiabatic passage

In this paper, we apply the Stark-chirped rapid adiabatic passage (SCRAP) technique by analogy and analysis to the field of nonlinear optical frequency conversion, and a third harmonic generation (THG) model based on the SCRAP technique is developed using the phase reversal quasi-phase matching (PRQPM) technique for nonlinear crystals. Nearly 100% conversion from a 636 nm laser to a 212 nm deep-ultraviolet (DUV) laser is achieved using this model. The conversion efficiency remains above 99% for crystal temperature fluctuations (0-140 °C). The simulation results also show that the intermediate process of the proposed model produces almost no second harmonic, ensuring that the energy is mainly transferred to the target DUV laser output, and the SCRAP mechanism produces a bandwidth of about 210 nm.