Scattering of surface plasmons by one-dimensional periodic nanoindented surfaces

TL;DR

This paper presents a theoretical analysis of how periodic nanoindented surfaces can control surface plasmon scattering, enabling their use as efficient reflectors or converters into collimated light with minimal indentations.

Contribution

It introduces a modal expansion method to optimize nanoindented arrays for plasmon reflection and conversion, demonstrating effective control with few indentations.

Findings

Array parameters can be tuned for Bragg reflection or plasmon-to-light conversion.

Few indentations are sufficient for full functional performance.

Converted light is highly collimated within a narrow cone.

Abstract

In this work, the scattering of surface plasmons by a finite periodic array of one-dimensional grooves is theoretically analyzed by means of a modal expansion technique. We have found that the geometrical parameters of the array can be properly tuned to achieve optimal performance of the structure either as a Bragg reflector or as a converter of surface plasmons into light. In this last case, the emitted light is collimated within a few degrees cone. Importantly, we also show that a small number of indentations in the array are sufficient to fully achieve its functional capabilities.