In this work, the performance of Ca₅(BO₃)₃F (CBF) single crystals was investigated for the third harmonic generation at 355 nm. A high energy conversion efficiency of 16.9% at 355 nm was reached using a two-conversion-stage setup. First, using a high peak power, passively Q-switched Nd³⁺:YAG/Cr⁴⁺:YAG microlaser based gain aperture in micro-MOPA, the second harmonic at 532 nm was achieved with lithium triborate (LBO) crystal, reaching 1.35 MW peak power. On a second step, laser pulses at 355 nm were generated using a 5 mm-long CBF crystal growth by TSSG method with energy, pulse duration and peak power of 479 µJ, 568 ps and 0.843 MW, respectively. These results are currently the highest reported for CBF material.

中文翻译：

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Ca ₅（BO ₃）₃ F非线性单晶中355 nm处三次谐波产生的高峰值功率近兆瓦激光脉冲

在这项工作中，研究了Ca ₅（BO ₃）₃ F（CBF）单晶在355 nm处三次谐波产生的性能。使用两个转换阶段的设置，在355 nm处达到了16.9％的高能量转换效率。首先，使用高峰值功率，被动调Q Nd ³⁺：YAG / Cr ⁴⁺：MOMO中基于YAG微激光器的增益孔径，用三硼酸锂（LBO）晶体实现了532 nm的二次谐波，达到1.35 MW峰值功率。第二步，通过TSSG方法使用5 mm长的CBF晶体生长产生355 nm的激光脉冲，其能量，脉冲持续时间和峰值功率分别为479 µJ，568 ps和0.843 MW。这些结果是目前报道的最高的CBF材料。