When an ultrafast optical pulse with high intensity propagates through transparent material a supercontinuum can be coherently generated by self‐phase modulation, which is essential to many photonic applications in fibers and integrated waveguides. However, the presence of dispersion causes stagnation of spectral broadening past a certain propagation length, requiring an increased input peak power for further broadening. Overcoming such spectral stagnation will be key to achieve practical integrated supercontinuum devices. Here, a concept is presented to drive supercontinuum generation with significantly lower input power by counteracting spectral stagnation via repeatedly alternating the sign of group velocity dispersion along the propagation. The effect is experimentally demonstrated in dispersion alternating fiber in excellent agreement with modeling, revealing almost an order of magnitude reduced peak power compared to uniform dispersion. Calculations also reveal a similar power reduction with integrated optical waveguides, simultaneously with a significant increase in flat bandwidth, which is important for on‐chip broadband photonics.

中文翻译：

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具有符号交替色散的媒体中的超连续谱生成

当高强度的超快光脉冲通过透明材料传播时，可通过自相位调制相干地产生超连续谱，这对于光纤和集成波导中的许多光子应用至关重要。但是，色散的存在会导致超过一定传播长度的光谱展宽停滞，需要增加输入峰值功率才能进一步展宽。克服这种频谱停滞将是实现实用的集成超连续谱设备的关键。在这里，提出了一个概念，通过沿传播反复交替改变组速度色散的符号来抵消频谱停滞，从而以较低的输入功率来驱动超连续谱的生成。实验证明，在色散交替光纤中，其效果与建模极为吻合，与均匀色散相比，峰值功率降低了近一个数量级。计算还显示出集成光波导的功率降低类似，同时扁平带宽显着增加，这对于片上宽带光子学非常重要。