Tanaka Kazuo, Katayama Kiyofumi, Tanaka Masahiro
Department of Electronics and Computer Engineering, Gifu University, Yanagido, Gifu City, Japan.
Opt Express. 2010 Jan 18;18(2):787-98. doi: 10.1364/OE.18.000787.
A numerical study of the nanofocusing of surface plasmon polaritons (SPPs) by a pyramidal structure on a rectangular aperture is performed by the volume integral equation method. It is possible to perform nanofocusing using this structure by using a linearly polarized wave as the incident wave. The focusing process of SPPs by the tip of the pyramidal structure has been demonstrated numerically. The characteristics of the focused optical field near the tip have been investigated in detail. It was found to be similar to that of monopole rather than that of a tiny dipole. The optical field at the tip is sensitive to the local shape of the tip. The enhanced intensity on the tip increases with an increase in the aperture width.
采用体积分方程法对矩形孔径上金字塔结构的表面等离激元极化激元（SPP）纳米聚焦进行了数值研究。通过使用线偏振波作为入射波，利用该结构实现纳米聚焦是可行的。通过数值方法证明了金字塔结构尖端对SPP的聚焦过程。详细研究了尖端附近聚焦光场的特性。发现其类似于单极子而非微小偶极子的特性。尖端处的光场对尖端的局部形状敏感。尖端上增强的强度随着孔径宽度的增加而增加。
