Omenetto F G, Wolchover N A, Wehner M R, Ross M, Efimov A, Taylor A J, Kumar V V R K, George A K, Knight J C, Joly N Y, Russell P St J
Opt Express. 2006 May 29;14(11):4928-34. doi: 10.1364/oe.14.004928.
The conversion of light fields in photonic crystal fibers (PCFs) capitalizes on the dramatic enhancement of several optical nonlinearities. We present here spectrally smooth, highly broadband supercontinuum radiation in a short piece of high-nonlinearity soft-glass PCF. This supercontinuum spans several optical octaves, with a spectral range extending from 350 nm to beyond 3000 nm. The selection of an appropriate propagation-length determines the spectral quality of the supercontinuum generated. Experimentally, we clearly identify two regimes of nonlinear pulse transformation: when the fiber length is much shorter than the dispersion length, soliton propagation is not important and a symmetric supercontinuum spectrum arises from almost pure self-phase modulation. For longer fiber lengths the supercontinuum is formed by the breakup of multiple Raman-shifting solitons. In both regions very broad supercontinuum radiation is produced.
光子晶体光纤（PCF）中光场的转换利用了几种光学非线性效应的显著增强。我们在此展示了在一小段高非线性软玻璃光子晶体光纤中产生的光谱平滑、高度宽带的超连续谱辐射。这种超连续谱跨越了几个光学倍频程，光谱范围从350纳米延伸至3000纳米以上。选择合适的传播长度可决定所产生超连续谱的光谱质量。通过实验，我们清楚地识别出非线性脉冲变换的两种状态：当光纤长度远短于色散长度时，孤子传播并不重要，几乎纯粹的自相位调制会产生对称的超连续谱。对于更长的光纤长度，超连续谱由多个拉曼频移孤子的分裂形成。在这两个区域都会产生非常宽的超连续谱辐射。
