Investigation of Surface Plasmon Resonance in Super-Period Gold Nanoslit Arrays

TL;DR

This paper investigates surface plasmon resonance in super-period gold nanoslit arrays, revealing how the small period determines resonance frequencies and that first order diffraction provides more accurate resonance wavelength measurements.

Contribution

It demonstrates that the small period of nanoslits controls resonance frequencies, and that first order diffraction better reveals the true surface plasmon resonance wavelength.

Findings

Resonance frequencies depend on the small period of nanoslits.

Number of nanoslits and slit width do not affect resonance frequencies.

First order diffraction offers more accurate resonance wavelength measurement.

Abstract

Surface plasmon resonance in super-period metal nanoslits can be observed in the first order diffraction as well in the zeroth order transmission. In this paper, surface plasmon resonance modes in various super-period gold nanoslit arrays are investigated. It is found that the surface plasmon resonance frequencies are determined by the small period of the nanoslits in super-period nanoslits. The number of nanoslits in the unit cell super-period and the nanoslit width do not control the surface plasmon resonance frequencies. It is also found that the resonance wavelength observed in the first order diffraction reveals more accurate the real surface plasmon resonance wavelength in the metal super-period nanoslit array device.