Abstract We theoretically investigate and propose a promising 8-mm-long cascade planar waveguide made of Si 3 N 4 and As 2 Se 3 glass system for mid-infrared supercontinuum generation by employing a commercially available femtosecond pump source operating at 1550 nm wavelength. A rigorous numerical investigation has been performed considering three different dispersion regions of the optimized cascade waveguide for expanding the SC coverage far into the mid-infrared. Based on the tailored dispersion region whether the anomalous or normal, the pump pulse is applied at the input of the initial waveguide segment of Si 3 N 4 and the output of which is then coupled into the final waveguide segment made of As 2 Se 3 glass system. The output supercontinuum spectrum for all-anomalous dispersion region expanded up to 10 μ m by one of the best reported so far using cascade design with coherency of unity over the entire spectrum region predicted. This would be the widest spectral coverage expanded into the mid-infrared, to the best of the authors’ knowledge, by the cascade planar waveguide design employing a commercially available pump source in telecommunication window with a peak power of 5 kW. Such a highly coherent cascade planar waveguide, designed and proposed based on the concatenating principle for a broadband mid-infrared supercontinuum generation using the two-step process, would be highly suitable for many mid-infrared based applications such as sensing and biological imaging.

中文翻译：

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电信波长泵浦源产生中红外超连续谱的色散工程级联通道波导分析与设计

摘要 我们从理论上研究并提出了一种有前途的 8 毫米长级联平面波导，该波导由 Si 3 N 4 和 As 2 Se 3 玻璃系统制成，通过使用在 1550 nm 波长下工作的市售飞秒泵浦源来产生中红外超连续谱。考虑到优化级联波导的三个不同色散区域，将 SC 覆盖范围扩展到中红外，进行了严格的数值研究。基于定制的色散区域，无论是异常还是正常，泵浦脉冲施加在 Si 3 N 4 初始波导段的输入端，然后其输出耦合到由 As 2 Se 3 玻璃制成的最终波导段系统。全反常色散区域的输出超连续谱扩展到 10 μm，是迄今为止报道的最好的一种，使用级联设计，预测整个光谱区域的一致性。据作者所知，这将是扩展到中红外的最宽光谱覆盖范围，通过级联平面波导设计在电信窗口中采用商用泵浦源，峰值功率为 5 kW。这种高度相干级联平面波导是基于使用两步法产生宽带中红外超连续谱的级联原理而设计和提出的，将非常适合许多基于中红外的应用，如传感和生物成像。据作者所知，这将是扩展到中红外的最宽光谱覆盖范围，通过级联平面波导设计在电信窗口中采用商用泵浦源，峰值功率为 5 kW。这种高度相干级联平面波导是基于使用两步法产生宽带中红外超连续谱的级联原理而设计和提出的，将非常适合许多基于中红外的应用，如传感和生物成像。据作者所知，这将是扩展到中红外的最宽光谱覆盖范围，通过级联平面波导设计在电信窗口中采用商用泵浦源，峰值功率为 5 kW。这种高度相干级联平面波导是基于使用两步法产生宽带中红外超连续谱的级联原理而设计和提出的，将非常适合许多基于中红外的应用，如传感和生物成像。