Magnetoplasma Modes in Alkali Metals

Abstract

It is shown that Fermi-liquid interactions in the alkali metals lead to a family of long-wavelength electromagnetic modes propagating parallel to a uniform magnetic field, near the cyclotron frequency. In contrast to the perpendicular case, however, there is a cutoff wavelength that increases with decreasing Fermi-liquid interaction, and can be in the range of 10 to 100 cyclotron radii, for the size of interaction now indicated in potassium.