Kim Kyoung-Youm, Chong Xinyuan, Ren Fanghui, Wang Alan X
Opt Lett. 2015 Nov 15;40(22):5339-42. doi: 10.1364/OL.40.005339.
In this Letter, we investigate the slow-light effect of subwavelength diffraction gratings via the Rayleigh anomaly using a fully analytical approach without needing to consider specific grating structures. Our results show that the local group velocity of the transmitted light can be significantly reduced due to the optical vortex, which can inspire a new mechanism to enhance light-matter interactions for optical sensing and photodetection. However, the slow-light effect will diminish as the transmitted light propagates farther from the grating surface, and the slowdown factor decreases as the grating size shrinks.
在本信函中，我们使用一种完全解析的方法，通过瑞利异常研究亚波长衍射光栅的慢光效应，而无需考虑特定的光栅结构。我们的结果表明，由于光学涡旋，透射光的局部群速度会显著降低，这可以激发一种新的机制来增强用于光学传感和光电探测的光与物质相互作用。然而，随着透射光远离光栅表面传播，慢光效应将会减弱，并且随着光栅尺寸缩小，减速因子也会减小。
