## Abstract

The anomalously-high transmission of light through sub-wavelength apertures is a phenomenon which has been observed in numerous experiments, but whose theoretical explanation is incomplete. In this article we present a numerical analysis of the power flow (characterized by the Poynting vector)of the electromagnetic field near a sub-wavelength sized slit in a thin metal plate, and demonstrate that the enhanced transmission is accompanied by the annihilation of phase singularities in the power flow near the slit.

© 2003 Optical Society of America

Full Article |

PDF Article
### Equations (9)

Equations on this page are rendered with MathJax. Learn more.

(1)
$$\mathbf{S}(x,z)=\frac{1}{2}\mathrm{Re}\left\{\hat{\mathbf{E}}(x,z)\times {\hat{\mathbf{H}}}^{*}(x,z)\right\},$$
(2)
$$\mathrm{sin}{\varphi}_{S}(x,z)\equiv \frac{{S}_{z}(x,z)}{\mid \mathbf{S}\mid},$$
(3)
$$\mathrm{cos}{\varphi}_{S}(x,z)\equiv \frac{{S}_{x}(x,z)}{\mid \mathbf{S}\mid},$$
(4)
$$\mathbf{S}(x,z)=-\frac{1}{2\omega {\mu}_{0}}\mathrm{Im}\{{\hat{E}}_{y}\nabla {\hat{E}}_{y}^{*}\}.$$
(5)
$${\hat{E}}_{y}(x,z)=\mid {\hat{E}}_{y}(x,z)\mid {e}^{\text{i}\varphi E(x,z)}.$$
(6)
$$\mathbf{S}(x,z)=\frac{1}{2\omega {\mu}_{0}}{\mid {\hat{E}}_{y}(x,z)\mid}^{2}\nabla \varphi E(x,z).$$
(7)
$${s}_{E}\equiv \frac{1}{2\pi}{\oint}_{C}\nabla {\varphi}_{E}\xb7\text{d}\mathbf{r},$$
(8)
$${\hat{E}}_{i}(x,z)={\hat{E}}_{i}^{\mathrm{inc}}(x,z)-i\omega \Delta \epsilon {\int}_{D}{\hat{G}}_{\mathit{ij}}^{E}(x,z;x\prime ,z\prime ){\hat{E}}_{j}(x\prime ,z\prime )\text{d}x\prime \text{d}z\prime ,$$
(9)
$$T\equiv \frac{{\int}_{\mathrm{slit}}{S}_{z}{d}^{2}x+{\int}_{\mathrm{plate}}\left({S}_{z}-{S}_{z}^{\mathrm{inc}}\right){d}^{2}x}{{\int}_{\mathrm{slit}}{S}_{z}^{\left(0\right)}{d}^{2}x}.$$