High efficiency cascaded third-harmonic generation in a quasi-periodically poled KTiOPO4 crystal
High efficiency cascaded third-harmonic generation in a quasi-periodically poled KTiOPO4 crystal
复制标题
准周期极化 KTiOPO4 晶体中的高效级联三次谐波产生
作者：
Augustin Vernay;Lucas Bonnet;V. Boutou;Sivan Trajtenberg‐Mills;A. Arie;B. Boulanger
我们在准周期极化 KTP (QPPKTP) 晶体中执行并研究了级联三次谐波生成 (THG)，允许两个级联步骤 ω + ω → 2ω 和 2ω + ω → 3ω 同时进行相位匹配。当 QPPKTP 晶体被加热到 95°C 时，在基本波长 λω = 1587 nm 处实现了相位匹配。对于 20 µJ 的基本能量（对应于 1.5 GW/cm2 的强度），能量转换效率在皮秒范围内达到 40%。据我们所知，这是有史以来报告的 THG 效率的最高值。泵耗尽情况下的建模准确地描述了实验。
We performed and studied cascaded third-harmonic generation (THG) in a quasi-periodically poled KTP (QPPKTP) crystal allowing simultaneous phase-matching of the two cascading steps ω + ω → 2ω and 2ω + ω → 3ω. The phase-matching was achieved at the fundamental wavelength λω = 1587 nm when the QPPKTP crystal was heated to 95°C. The energy conversion efficiency reached 40% in the picosecond regime for a fundamental energy of 20 µJ that corresponds to an intensity of 1.5 GW/cm2. It is the highest value of THG efficiency ever reported to the best of our knowledge. The modeling in the case of the depleted pump regime accurately described the experiments.