Surface Plasmonic Lattice Solitons in Semi-infinite Graphene Sheet Arrays

TL;DR

This paper explores the formation and control of surface plasmonic lattice solitons in semi-infinite graphene arrays, demonstrating deep-subwavelength confinement and potential for optical switching applications.

Contribution

It introduces the concept of surface plasmonic lattice solitons in graphene arrays and shows how their propagation can be controlled via power and chemical potential.

Findings

Surface PLSs are formed when SPP tunneling is inhibited by nonlinearity.

Surface PLSs can be confined to ~0.001λ scale.

Propagation can be switched by adjusting power or chemical potential.

Abstract

We investigate the surface plasmonic lattice solitons (PLSs) in semi-infinite graphene sheet arrays. The surface soliton is formed as the SPPs tunneling is inhibited by the graphene nonlinearity, and meanwhile the incident power should be above a threshold value. Thanks to the strong confinement of surface plasmon polaritons (SPPs) on graphene, the effective width of surface PLSs can be squeezed into deep-subwavelength scale of ~ 0.001{\lambda}. Based on the stable propagation of surface PLSs, we find that the light propagation can be switched from the array boundary to the inner graphene sheets by reducing the incident power or increasing the chemical potential of graphene. The study may find promising application in optical switches on deep-subwavelength scale.