In the present study, the transmission characteristics of ultrashort pulses through coupled-cavity waveguides in one-dimensional photonic crystals were investigated theoretically, using finite-difference time-domain and transfer matrix methods. By controlling the configuration of the waveguides, a flat defects’ band can be obtained in the transmission spectra, which can be used for passing ultrashort pulses. The conditions for achieving a flat defects’ band are derived by optimization geometrical parameters of the waveguides. The optimized structure is able to transmit ultrashort pulses, up to 30 fs, with negligible distortion and attenuation. Unlike the previously designed waveguides with the same application, we designed our system without using graded index materials or many thin film layers.

中文翻译：

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传输超短脉冲的一维耦合腔光子晶体波导平面缺陷带的设计

在本研究中，从理论上研究了超短脉冲通过一维光子晶体中耦合腔波导的传输特性，使用有限差分时域和传输矩阵方法。通过控制波导的配置，可以在透射光谱中获得平坦的缺陷带，可用于通过超短脉冲。获得平坦缺陷带的条件是通过优化波导的几何参数得出的。优化的结构能够传输高达 30 fs 的超短脉冲，失真和衰减可以忽略不计。与之前设计的具有相同应用的波导不同，我们设计的系统没有使用渐变折射率材料或许多薄膜层。