Scattering-free routing of surface plasmon polariton waves with optical null medium

TL;DR

This paper introduces a transformation optics-based method to route surface plasmon polariton waves along arbitrary paths without scattering losses, using a homogeneous material that simplifies fabrication and enhances nano-optic device performance.

Contribution

A novel, geometry-independent material design for scattering-free SPP routing at metal-dielectric interfaces using transformation optics.

Findings

Successfully demonstrated scattering-free SPP guidance in simulations.

Material remains homogeneous regardless of bump shape.

Potential to advance nano-optics and photonic circuit miniaturization.

Abstract

Recently, guiding electromagnetic surface waves without sacrificing scattering losses through paths that have arbitrary shape bumps has gained a lot of interest due to its wealth of advantages in modern photonics and plasmonics devices. In this study, based on transformation optics (TO) methodology, a feasible approach to control the flow of surface plasmon plariton (SPPs) at metal-dielectric interfaces with arbitrary curvature is proposed. The obtained material becomes homogeneous and independent of the bump's geometry. That is, one constant material is required to route SPP waves without scattering the energy into the far-field region, which overcome the bottlenecks encountered in the previous works. Several numerical simulations are carried out to illustrate the capability of the propounded cloak to control the SPP flows at metal/dielectric interfaces. The unique designing approach introduced here may open a new horizon to nano-optics and downscaling of photonic circuits.