Jiang An-Qing, Zang Kai-Yan, Hu Er-Tao, Tu Hua-Tian, Xu Lei, Ren Wen-Shuai, Yoshie Osamu, Lee Young-Pak, Zheng Yu-Xiang, Wang Song-You, Zhao Hai-Bin, Guo Jun-Peng, Wang C Z, Ho K M, Lynch David W, Chen Liang-Yao
Department of Optical Science and Engineering, Fudan University, Shanghai, China.
Graduate School of IPS, Waseda University, Fukuoka, Japan.
Sci Rep. 2019 Aug 27;9(1):12434. doi: 10.1038/s41598-019-48938-z.
In this work, the two-dimensional profile of the light transmission through a prism-like metallic film sample of Au was measured at a wavelength of 632.8 nm in the visible intraband transition region to verify that, beyond the possible mechanisms of overcoming the diffraction limit, a strongly nonuniform optical absorption path length of the light traveling in the metal could induce a lensing effect, thereby narrowing the image of an object. A set of prism-like Au samples with different angles was prepared and experimentally investigated. Due to the nonuniform paths of the light traveling in the Au samples, lens-effect-like phenomena were clearly observed that reduced the imaged size of the beam spot with decreasing light intensity. The experimental measurements presented in the work may provide new insight to better understand the light propagation behavior at a metal/dielectric interface.
在这项工作中，在可见光带内跃迁区域，于波长632.8 nm处测量了通过类棱镜金金属薄膜样品的光透射二维轮廓，以验证除了克服衍射极限的可能机制外，光在金属中传播时强烈不均匀的光吸收路径长度可引发透镜效应，从而缩小物体图像。制备了一组具有不同角度的类棱镜金样品并进行了实验研究。由于光在金样品中传播路径不均匀，清晰观察到类似透镜效应的现象，随着光强降低，光斑的成像尺寸减小。该工作中呈现的实验测量结果可能为更好地理解金属/电介质界面处的光传播行为提供新的见解。
