Efficient Generation of Red and Blue Light in a Dual-StructurePeriodically Poled LiTaO₃ Crystal

We demonstrate the efficient generation of red light at 671 nm and blue light at 447 nm from a diode-pumped Q-switched 1342 nm Nd:YVO₄ laser together with a periodically poled LiTaO₃ (PPLT) crystal. The sample used in this experiment is a dual-structure PPLT crystal with the period of 14.9 μm for the second harmonic generation and that of 4.9 μm for the third harmonic generation. The red and blue light, with the respective average power of 752 mW and 153 mW were obtained in a single path under an average fundamental power of 1.74 W, corresponding to the conversion efficiencies of 43.2% and 8.8%, respectively. These results indicate that the dual-structure PPLT can be used to construct a compact and efficient all-solid-state red-and-blue dual-wavelength laser.