Surface Waves and Forced Oscillations in QHE Planar Samples

TL;DR

This paper derives the dispersion relations and polarization characteristics of surface waves and forced oscillations in quantum Hall effect planar samples, revealing their potential to support infrared excitations and explaining recent edge resonances.

Contribution

It provides explicit formulas for surface wave properties in QHE samples and introduces a qualitative model for edge resonances based on these solutions.

Findings

Surface waves can exist in millimetric QHE samples at infrared frequencies.

Forced oscillations show an almost frequency-independent wavelength decreasing with magnetic field.

A qualitative model explains recently observed edge resonances in 2DEG under QHE conditions.

Abstract

Dispersion relations and polarizations for surface waves in infinite planar samples in the QHE regime are explicitly determined in the small wavevector limit in which the dielectric tensor can be considered as local. The wavelength and frequency regions of applicability of the results extends to the infrared region for typical experimental conditions. Then, standard samples with millimetric sizes seem to be able to support such excitations. Forced oscillations are also determined which should be generated in the 2DEG by external electromagnetic sources. They show an almost frequency independent wavevelength which decreases with the magnetic field. A qualitative model based in these solutions is also presented to describe a recently found new class of resonances appearing near the edge of a 2DEG in the QHE regime.