Terahertz resonances due to edge magnetoplasmons in a wide armchair graphene ribbon with a weak superlattice potential

Abstract

A strong modulation of the resonance frequencies and the gaps of edge magnetoplamons (EMPs), in the ribbon at the ν = 2 quantum Hall effect regime with a superlattice and a smooth steplike electrostatic lateral potential, due to a modulation of the interedge distance is shown. We obtain that, in a wide range of the interedge distances, within THz region the EMPs show wide frequency gaps and at peculiar frequencies the response of the system should manifest resonances. For the latter frequencies the group velocities are nullified

Spatial dispersion of magnetic-edge magnetoplasmons: Effect of semi-infinite gate

“…These EMPs appear due to a strong change of the stationary local electron density at the edge of the channel (in particular, in the vicinity of edge states) that induces a strong modulation of the local magnetoconductivity tensor; modulation of the nondiagonal components is especially important [1,2,5,8,9,13]. In addition, EMPs in graphene have attracted attention recently [18][19][20][21][22][23][24][25].…”