One-dimensional plasmons confined in bilayer graphene p-n junctions

TL;DR

This paper investigates how guided plasmon modes in bilayer graphene p-n junctions can be controlled via in-plane and perpendicular electric fields, affecting their spectrum and propagation direction.

Contribution

It introduces a hydrodynamic model to analyze guided plasmon spectra in bilayer graphene p-n junctions with electric field tunability.

Findings

Plasmon modes can be guided along the p-n junction line.

Electric fields allow control over plasmon propagation direction.

Perpendicular electric field opens a band gap, influencing plasmon behavior.

Abstract

Gapless spectrum of graphene allows easy spatial separation of electrons and holes with an external in-plane electric field. Guided collective plasmon modes can propagate along the separation line, whose amplitude decays with the distance to it. Their spectrum and direction of propagation can be controlled with the strength and direction of in-plane electric field. In case of a bilayer graphene additional control is possible by the perpendicular electric field that opens a gap in the band spectrum of electrons. We investigate guided plasmon spectra in bilayer p-n junctions using hydrodynamics of charged electron liquid.