Edge magnetoplasmons in a wide armchair graphene ribbon with a weak superlattice potential: finite frequency gaps and zero group velocity

Abstract

We show strong effects of a weak and smooth, on the magnetic length, superlattice potential upon edge magnetoplasmons (EMPs) at the armchair edge, with a smooth steplike electrostatic lateral confining potential, of a wide graphene channel in the $\nu =2$ quantum Hall effect regime. The superlattice potential leads to essential enlargement of a number of EMPs, descend from two fundamental EMPs in the absence of superlattice. For the wave vector $k_x$ within the first Brillouin zone, the EMPs show as the regions of acoustical or quasi-acoustical dispersion, with a finite value of group velocity, so the regions with frequency gaps, where a group velocity is nullified at some $k_x$. We obtain that for $k_x\to 0$ only for two EMPs the frequency tends to zero as for other EMPs it obtains finite values. Strong dependence of dispersion relations of the EMPs from the period of the superlattice $a_0$ and the distance $d$ from a metallic gate is shown; in particular, for typical size of a gap, for characteristic value of the frequency and $k_x$ at which the group velocity is reduced to zero. At the frequency that corresponds to zero group velocity of pertinent fundamental EMP branch the response of the system should present a strong resonance.

arXiv comment11 pages, 10 figures

References in corpus (29)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• Two Dimensional Atomic Crystals
• Chiral tunneling and the Klein paradox in graphene
• Electronic Properties of Disordered Two-Dimensional Carbon
• Unconventional Integer Quantum Hall effect in graphene
• Quantum Transport in Semiconductor Nanostructures
• Spin Filtered Edge States and Quantum Hall Effect in Graphene
• Edge States and the Quantized Hall Effect in Graphene
• Klein Backscattering and Fabry-Perot Interference in Graphene Heterojunctions
• Extra Dirac points in the energy spectrum for superlattices on single-layer graphene
• Emerging Zero Modes for Graphene in a Periodic Potential
• Dirac and Klein-Gordon particles in one-dimensional periodic potentials
• Dirac Fermion Confinement in Graphene
• Novel Edge Excitations of Two-dimensional Electron Liquid in a Magnetic Field
• Landau Levels and Quantum Hall Effect in Graphene Superlattices
• The Fock-Darwin States of Dirac Electrons in Graphene-based Artificial Atoms
• Charge and Spin Transport at the Quantum Hall Edge of Graphene
• Edge states, mass and spin gaps, and quantum Hall effect in graphene
• Dispersion Law of Edge Waves in the Quantum Hall Effect
• Edge states on graphene ribbon in magnetic field: interplay between Dirac and ferromagnetic-like gaps
• Hot carriers in an intrinsic graphene
• Plasmon Modes and Correlation Functions in Quantum Wires and Hall Bars
• Collective Edge Excitations In The Quantum Hall Regime: Edge Helicons And Landau-level Structure
• Random-phase Approximation Treatment Of Edge Magnetoplasmons: Edge-state Screening And Nonlocality
• Hot carriers in a bipolar graphene
• Temperature Effects on Edge Magnetoplasmons in the Quantum Hall Regime
• Edge magnetoplasmons in periodically modulated structures
• Edge helicons and repulsion of fundamental edge magnetoplasmons in the quantum Hall regime