Simple approach to broadband mid-infrared pulse generation with a mode-locked Yb-doped fiber laser
Simple approach to broadband mid-infrared pulse generation with a mode-locked Yb-doped fiber laser
复制标题
DOI：
10.1364/ol.450921
复制
发表时间：
2022-04-01
期刊：
影响因子：
3.6
通讯作者：
Ideguchi, Takuro
中科院分区：
文献类型：
--
作者：
Nakamura, Takuma;Badarla, Venkata Ramaiah;Ideguchi, Takuro
宽带中红外（MIR）分子光谱技术要求在分子指纹区有一个明亮的宽带光源。为此，脉冲内差频产生（IDFG）在各种技术中表现出优异的性能。尽管使用1.5或2 μ m超短脉冲激光器泵浦的IDFG系统已经得到了广泛的发展，但很少有系统使用1 μ m激光器，即使用体积庞大的100 w级高功率薄片状激光器。在这项工作中，我们展示了一种简单而稳健的方法，即使用传统的锁模掺镱光纤激光器实现1 μ m泵浦宽带IDFG。我们首先通过短单模光纤的光谱加宽和啁啾反射镜的脉冲压缩的简单组合，在50MHz产生3.3 w， 12.1 fs的超短脉冲。然后，我们使用它们泵送一个薄的定向图案磷化镓晶体，在指纹区域（760-1240 cm- 1,8.1 -13.1 μ m）产生1.2 mw宽带MIR脉冲，其-20 db带宽为480 cm（-1）。基于1 μ m的IDFG系统允许在紫外和可见光区域产生额外的超短脉冲，例如，实现50 mhz级别的高重复率振动和频率产生光谱或泵浦探测光谱。(C) 2022光学出版集团
Broadband mid-infrared (MIR) molecular spectroscopy demands a bright and broadband light source in the molecular fingerprint region. To this end, intra-pulse difference frequency generation (IDFG) has shown excellent properties among various techniques. Although IDFG systems pumped with 1.5- or 2-mu m ultrashort pulsed lasers have been extensively developed, few systems have been demonstrated with 1-mu m lasers, which use bulky 100-W-class high-powerYbthin-disk lasers. In this work, we demonstrate a simple and robust approach of 1-mu m-pumped broadband IDFG with a conventional mode-locked Yb-doped fiber laser. We first generate 3.3-W, 12.1-fs ultrashort pulses at 50MHz by a simple combination of spectral broadening with a short single-mode fiber and pulse compression with chirped mirrors. Then, we use them for pumping a thin orientation-patterned gallium phosphide crystal, generating 1.2-mW broadband MIR pulses with the -20-dB bandwidth of 480 cm(-1) in the fingerprint region (760-1240 cm-1, 8.1-13.1 mu m). The 1-mu m-based IDFG system allows for additional generations of ultrashort pulses in the ultraviolet and visible regions, enabling, for example, 50-MHz-level high-repetition-rate vibrational sum-frequency generation spectroscopy or pump-probe spectroscopy. (C) 2022 Optica Publishing Group