Comparative study of second harmonic generation at 1030 nm in BiBO and LBO crystals using a 100 W-class picosecond laser

TL;DR

This study experimentally compares the efficiency and properties of BiBO and LBO crystals for second harmonic generation at 1030 nm using a high-power picosecond laser, providing benchmarks for crystal selection.

Contribution

It offers the first direct quantitative comparison of BiBO and LBO crystals under high-power ultrashort pulse conditions for SHG at 1030 nm.

Findings

Both crystals achieved 32 W SH output at 515 nm with 56% efficiency.

BiBO achieved the highest SH output power reported in the green region with this setup.

The study characterizes power dependence, stability, beam quality, and other properties for both crystals.

Abstract

We present a systematic experimental comparison of single-pass second-harmonic generation (SHG) in bismuth triborate (BiBO) and lithium triborate (LBO) nonlinear crystals, driven by a 1.3 ps, 91 kHz laser at 1030 nm with up to 57 W of average input power. Both crystals yielded 32 W of second harmonic (SH) output at 515 nm, corresponding to a conversion efficiency of 56 %, which to the best of our knowledge represents the highest SH output power reported in the green spectral region using a BiBO crystal. Power dependence, long-term stability, beam quality, pulse duration, spectral properties, thermal effects, and angular acceptance bandwidth are characterized and directly compared for both crystals. These results provide quantitative performance benchmarks to guide the selection of nonlinear crystals for high-average-power, ultrashort-pulse frequency conversion near 1030 nm.