Plasmon-Polariton Waves in Nanofilms on One-Dimensional Photonic Crystal Surfaces

TL;DR

This paper presents a unified impedance-based approach to analyze plasmon-polariton waves on 1-D photonic crystal surfaces, deriving a dispersion relation and design method for long-range surface wave propagation.

Contribution

It introduces a comprehensive impedance method for both polarizations and provides a design framework for optimizing long-range plasmon-polariton waves on 1-D photonic crystal surfaces.

Findings

Derived a general dispersion relation for surface waves in 1-D PCs.

Established conditions for long-range propagation of plasmon-polaritons.

Showed wavelength tuning can maximize propagation length.

Abstract

The propagation of bound optical waves along the surface of a one-dimensional (1-D) photonic crystal (PC) structure is considered. A unified description of the waves in 1-D PCs for both s- and p-polarizations is done via an impedance approach. A general dispersion relation that is valid for optical surface waves with both polarizations is obtained, and conditions are presented for long-range propagation of plasmon-polariton waves in nanofilms (including lossy ones) deposited on the top of the 1-D PC structure. A method is described for designing 1-D PC structures to fulfill the conditions required for the existence of the surface mode with a particular wavevector at a particular wavelength. It is shown that the propagation length of the long-range surface plasmon-polaritons can be maximized by wavelength tuning, which introduces a slight asymmetry in the system.