Analysis of a metallic nano-rod polarizer using finite-difference-time-domain method

TL;DR

This paper investigates how metallic nano-rod arrays influence light polarization using FDTD simulations, revealing conditions for polarization reversal and designing high-performance nano-rod polarizers.

Contribution

It provides a detailed analysis of polarization behavior in nano-rod layers and proposes design principles for efficient nano-rod polarizers based on spacing and layering.

Findings

Spacing less than half wavelength causes parallel polarization reflection.

Spacing greater than half wavelength leads to perpendicular polarization absorption.

Multiple layers improve polarizer extinction ratio and transmittance.

Abstract

The polarization behavior of metallic nano-rods has been analyzed by means of the finite-difference-time-domain method. When the average spacing between the nano-rods is less than a half wavelength, the layer reflects the light polarized parallel to the nano-rods, as in a nano-slit. However, when the spacing is larger than a half wavelength, the metallic surface absorbs the light, polarized perpendicular to the rods, leading to a polarization reversal. Multiple layers of nano-rods can make a polarizer with a high extinction ratio and good transmittance.