Tripepi Michael, Barrette Andrew, Ferdinandus Manuel, Eshel Ben, Averett Kent L, Chowdhury Enam A, Liebig Carl M
Appl Opt. 2021 Sep 1;60(25):G126-G131. doi: 10.1364/AO.427709.
Yttrium aluminum garnet (YAG) is a common host material for both bulk and single-crystal fiber lasers. With increasing interest in developing optical technologies in the short-wave infrared and mid-infrared wavelength range, YAG may be a potential supercontinuum medium for these applications. Here, we characterize femtosecond laser pumped supercontinuum generation with 1200-2000 nm pump wavelengths () for undoped, single-crystal YAG fibers, which are representative of the normal, zero, and anomalous-dispersion regimes. Supercontinuum was observed over the spectral region of about 0.2 to 1.6. Z-scan measurements were also performed of bulk YAG, which revealed little dispersion of the nonlinear index of refraction () in the region of interest. The measured values of (∼1×10/) indicate a regime in which the nonlinear length, , is less than the dispersion length, , (≪). We report intensity clamping of the generated filament in the normal group velocity dispersion (GVD) regime and an isolated anti-Stokes peak in the anomalous GVD regime, suggesting further consideration is needed to optimize supercontinuum generation in this fiber medium.
钇铝石榴石（YAG）是一种常用于块状和单晶光纤激光器的基质材料。随着人们对开发短波红外和中红外波长范围内光学技术的兴趣日益浓厚，YAG可能是这些应用的一种潜在超连续谱介质。在此，我们对未掺杂的单晶YAG光纤在1200 - 2000 nm泵浦波长（）下飞秒激光泵浦产生的超连续谱进行了表征，这些光纤代表了正常色散、零色散和反常色散区域。在约0.2至1.6的光谱区域观察到了超连续谱。还对块状YAG进行了Z扫描测量，结果表明在感兴趣的区域非线性折射率（）几乎没有色散。所测得的（约1×10/）值表明处于非线性长度小于色散长度（≪）的状态。我们报告了在正常群速度色散（GVD）区域所产生细丝的强度钳制以及在反常GVD区域出现的一个孤立反斯托克斯峰，这表明需要进一步考虑优化这种光纤介质中的超连续谱产生。
