State Key Laboratory of Modern Optical Instrumentation, Department of Physics, Zhejiang University, Hangzhou 310027, China.
State Key Laboratory of Modern Optical Instrumentation, College of Optical Engineering, Zhejiang University, Hangzhou 310027, China.
Nat Commun. 2017 May 19;8:15391. doi: 10.1038/ncomms15391.
Optical analog computing offers high-throughput low-power-consumption operation for specialized computational tasks. Traditionally, optical analog computing in the spatial domain uses a bulky system of lenses and filters. Recent developments in metamaterials enable the miniaturization of such computing elements down to a subwavelength scale. However, the required metamaterial consists of a complex array of meta-atoms, and direct demonstration of image processing is challenging. Here, we show that the interference effects associated with surface plasmon excitations at a single metal-dielectric interface can perform spatial differentiation. And we experimentally demonstrate edge detection of an image without any Fourier lens. This work points to a simple yet powerful mechanism for optical analog computing at the nanoscale.
光学模拟计算为特定的计算任务提供了高吞吐量、低功耗的操作。传统上，基于空间域的光学模拟计算采用庞大的透镜和滤波器系统。最近的超材料发展使得这些计算元件能够小型化到亚波长尺度。然而，所需的超材料由复杂的亚波长单元组成，直接进行图像处理具有挑战性。在这里，我们展示了在单个金属-电介质界面上表面等离激元激发相关的干涉效应可以进行空间微分。我们通过实验演示了无需傅里叶透镜的图像边缘检测。这项工作为纳米尺度的光学模拟计算提供了一种简单而强大的机制。
