Differential sub-picosecond ultraviolet output from LiB 3 O 5 versus β -BaB 2 O 4 crystals under different frequency conversion conditions

Abstract We investigated the differences in sub-picosecond ultraviolet laser pulses generated via frequency conversion of LiB 3 O 5 (LBO) and β -BaB 2 O 4 (BBO) crystals under varying experimental conditions, with the incorporation of a delay line. For second harmonic generation, the LBO crystal yielded an optimal output power of 15.36 W, corresponding to a conversion efficiency of approximately 55.45%. For frequency tripling, the maximum output powers were 5.61 W (LBO crystal) and 4.50 W (BBO crystal), with peak conversion efficiencies reaching 20.26% and 16.25%, respectively. These experimental results not only illustrate the distinct frequency tripling performance between the LBO and BBO crystals but also validate the effectiveness of the delay line in facilitating efficient frequency conversion.