Study of Optical Properties of a Pinhole Nanorod

In this paper, the optical properties of a pinhole nanorod are studied using finite element package (COMSOL Multiphysics). Both electric and magnetic field distribution for different radius of a hollow nanorod and variable pinhole position has been measured. Furthermore, the scattering cross-section for both fields is calculated. The magnetic field enhancement has been increased by adding a pinhole made of air. The magnetic field enhancement improved 20 percent. In case of scattering cross-section, the response is changed as a function of the pinhole position and diameter. The results provide the ability to tune optical properties through an appropriate geometric feature of the nanorods.