We demonstrate a 266 nm ultraviolet (UV) picosecond laser by fourth-harmonic generation of a Nd:YAG laser with a 5.4 mm thick ${\mathrm{NaSr}}_3{\mathrm{Be}}_3{\mathrm{B}}_3{\mathrm{O}}_9{\mathrm{F}}_4$ (NSBBF) crystal. A maximum output power exceeding 1 W at 266 nm was obtained (the highest output power being 1.6 W), corresponding to a conversion efficiency of 10.3%. The stability measurements on the NSBBF crystal with a fluctuation of 3.34% at 200 mW within 1 h indicate that it is a promising UV nonlinear optical material for practical applications. In addition, for the first time, to the best of our knowledge, we measured the effective nonlinear coefficient of NSBBF crystal at 266 nm and compared it with that of $\beta -{\mathrm{BaB}}_2{\mathrm{O}}_4$ crystal.

中文翻译：

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使用NaSr ₃ Be ₃ B ₃ O ₉ F ₄晶体产生高功率266 nm激光

我们通过5.4毫米厚Nd：YAG激光的第四谐波产生演示了266 nm紫外（UV）皮秒激光 ${\mathrm{钠盐}}_3{是}_3{\mathrm{乙}}_3{\mathrm{Ø}}_9{\mathrm{F}}_4$（NSBBF）晶体。获得了在266 nm处超过1 W的最大输出功率（最高输出功率为1.6 W），对应于10.3％的转换效率。对NSBBF晶体进行的稳定性测量表明，在1小时内在200 mW下波动为3.34％，这是一种有希望的实用的UV非线性光学材料。此外，据我们所知，我们首次测量了NSBBF晶体在266 nm处的有效非线性系数，并将其与$\beta -{钡}_{\mathrm{2个}}{\mathrm{Ø}}_4$ 水晶。