Highly nonlinear multimode optical integrated devices hold great promise for the emerging large-capacity mode division multiplexing (MDM) technology, and they correspondingly enable multimode optical signal processing at nodes of the MDM network. Here, we propose a highly nonlinear multimode organic-silicon slot waveguide (HN-OSSW) whose nonlinearity is greatly improved by the intensive optical field confinement in the nano-gaps filled with highly nonlinear organic material. Specifically, the achieved nonlinear coefficients of the HN-OSSW under TE0 and TE1 modes are estimated higher than 7000 W−1m−1 and 5800 W−1m−1, respectively. Also, by phase mismatch optimization, this nanostructure exhibits superior intramode four-wave mixing conversion efficiency but ignorable intermode crosstalk. Coupling efficiency of the mode multiplexer and the optimal nonlinear interaction length are discussed in detail. Based on the HN-OSSW, we then numerically demonstrate a multimode all-optical hexadecimal addition and subtraction for sixteen phase-shift keying (16PSK) signals with the operation rate of 1.28Tb/s. Six different logic operations including A+B-C, A+C-B, B+C-A, A+B, A-B and B-A are simultaneously obtained with good performance evaluations, indicating the promising prospect of the HN-OSSW applied in ultrafast multimode signal processing.

中文翻译：

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用于超快多模全光逻辑运算的高度非线性有机硅缝隙波导

高度非线性的多模光集成器件为新兴的大容量模分复用（MDM）技术提供了广阔的前景，它们相应地在MDM网络的节点上实现了多模光信号处理。在这里，我们提出了一种高度非线性的多模有机硅缝隙波导（HN-OSSW），其非线性通过在填充高度非线性有机材料的纳米间隙中的强光场限制而大大提高。具体而言，在 TE0 和 TE1 模式下，HN-OSSW 的非线性系数估计分别高于 7000 W-1m-1 和 5800 W-1m-1。此外，通过相位失配优化，该纳米结构表现出优异的模内四波混频转换效率，但可忽略模间串扰。详细讨论了模式多路复用器的耦合效率和最佳非线性相互作用长度。然后，基于HN-OSSW，我们对16个相移键控（16PSK）信号以1.28Tb/s的运算速率进行了多模全光十六进制加减运算。同时得到A+BC、A+CB、B+CA、A+B、AB、BA六种不同的逻辑运算，性能评价良好，表明HN-OSSW在超快多模信号处理中的应用前景广阔。