Charge-Density Excitation on a Lateral Surface of a Semiconductor Superlattice and Edge Plasmons of a Two-Dimensional Electron Gas

On the lateral surfaces of a semiconductor superlattice, the structure along the direction of the superlattice axis displays the superlattice periodicity while along the perpendicular direction it is translationally invariant. We investigate the surface-plasma and magnetoplasma modes of such a surface as a function of the components of the wave vector along these two dissimilar directions.