Abstract

Metallic nano structures exhibit interesting optical properties due to the coupling of surface plasmon resonances with the electromagnetic fields. Metal nano particles exhibit dramatic field enhancement in the vicinity of the nano particle which can be further increased by near field coupling between closely spaced particles. In this paper, we study a system made of 3 nano cylinders placed at the vertices of an equilateral triangle. Near field optical responses of the system of silver nano cylinders interacting with the incident plane wave was simulated by finite difference time domain (FDTD) method in the visible light region. We attempt to study influences of the radius of the nano cylinders and inter-particle distances on the resonances.

Key words: Plasmons, FDTD, silver nano cylinder.