title: Temperature-insensitive frequency tripling for generating high-average power UV lasers.
abstract: Aimed for generating high-average power ultraviolet (UV) lasers via third-harmonic generation (THG) consisting of frequency doubling and tripling stages, we numerically and experimentally demonstrate a novel frequency tripling scheme capable of supporting temperature-insensitive phase-matching (PM). Two cascaded tripling crystals, with opposite signs of the temperature derivation of phase-mismatch, are proposed and theoretically studied for improving the temperature-acceptance of PM. The proof-of-principle tripling experiment using two crystals of LBO and BBO shows that the temperature acceptance can be ~1.5 times larger than that of using a single tripling crystal. In addition, the phase shift caused by air dispersion, along with its influence on the temperature-insensitive PM, are also discussed. To illustrate the potential applications of proposed two-crystal tripling design in the high-average-power regime, full numerical simulations for the tripling process, are implemented based on the realistic crystals. The demonstrated two-crystal tripling scheme may provide a promising route to high-average-power THG in the UV region.
authors.forename: Haizhe
authors.initials: H
authors.lastname: Zhong
authors.forename: Peng
authors.initials: P
authors.lastname: Yuan
authors.forename: Shuangchun
authors.initials: S
authors.lastname: Wen
authors.forename: Liejia
authors.initials: L
authors.lastname: Qian