Optical complex-valued convolution can extract the feature of complex-valued data by processing both amplitude and phase information, enabling a wide range of future applications in artificial intelligence and high-speed optical computation. However, because optical signals at different wavelengths cannot interfere, optical systems based on wavelength multiplexing usually can only realize real-valued computation. Here, we experimentally demonstrate an all-optical computing scheme using Kerr-based optical four-wave mixing (FWM) that can perform complex-valued convolution of multi-wavelength signals. Specifically, this all-optical complex-valued convolution operation can be implemented based on the coherent superposition of converted light generated by multiple FWM processes. The computational throughput of this scheme can be expanded by increasing the number of optical wavelengths and the signal baud rate. To exemplify the application, we successfully applied this all-optical complex-valued convolution to four different orientations of image edge extraction. Our scheme can provide a basis for wavelength-parallel optical computing systems with the demanded complex-valued computation capability.

中文翻译：

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基于四波混频的全光复值卷积

光学复值卷积可以通过处理幅度和相位信息来提取复值数据的特征，从而在人工智能和高速光学计算中实现广泛的未来应用。然而，由于不同波长的光信号不能干涉，基于波长复用的光学系统通常只能实现实值计算。在这里，我们实验性地演示了一种使用基于克尔的光学四波混频（FWM）的全光计算方案，该方案可以执行多波长信号的复值卷积。具体来说，这种全光复值卷积运算可以基于多个FWM过程产生的转换光的相干叠加来实现。该方案的计算吞吐量可以通过增加光波长数量和信号波特率来扩展。为了举例说明该应用，我们成功地将这种全光学复值卷积应用于图像边缘提取的四个不同方向。我们的方案可以为具有所需复值计算能力的波长并行光学计算系统提供基础。