Graphene waveguide induced by gradually varied magnetic fields

Abstract

A different way of producing the magnetic waveguide by loading gradually varied magnetic fields on graphene is proposed. The vector potential induced by the magnetic fields is connected by two square magnetic barriers and one magnetic well with linear variation. We investigate the guided modes and probability current density distribution within the graphene waveguide. It provides channels freely propagating and enables strong confinement for the modes by the gradually varied magnetic fields. The guide modes are caused by the electron reflection at the interfaces of the magnetic barriers. At the specific incident energy of electrons, there exist stable waveguide modes analogous to those in an optical waveguide. The hierarchy of guided modes decreases with the increasing incident angles. We hope that these results may lead to the potential applications in graphene-based waveguide structure.