Universal description of channel plasmons in two-dimensional materials

TL;DR

This paper introduces a universal effective-index method to describe channel plasmon-polaritons in 2D materials like graphene, enabling precise control and design of subwavelength photonic waveguides for future optoelectronic applications.

Contribution

The authors develop a universal Schrödinger-like equation to characterize 2D material channel plasmons, applicable across different geometries and validated against rigorous theories.

Findings

Accurate dispersion relations for graphene CPPs derived

Universal equation applicable to various 2D materials

Potential for deep subwavelength light guiding in photonic devices

Abstract

Channeling surface plasmon-polaritons to control their propagation direction is of the utmost importance for future optoelectronic devices. Here, we develop an effective-index method to describe and characterize the properties of 2D material's channel plasmon-polaritons (CPPs) guided along a V-shaped channel. Focusing on the case of graphene, we derive a universal Schr\"odinger-like equation from which one can determine the dispersion relation of graphene CPPs and corresponding field distributions at any given frequency, since they depend on the geometry of the structure alone. The results are then compared against more rigorous theories, having obtained a very good agreement. Our calculations show that CPPs in graphene and other 2D materials are attractive candidates to achieve deep subwavelength waveguiding of light, holding potential as active components for the next generation of tunable photonic devices.