SELF-CONSISTENT PHONON AND MAGNETOPHONON AND CUBIC ANHARMONIC CORRECTIONS OF THE 2D ELECTRON LATTICE

Anharmonic corrections to the phonon and magnetophonon spectrum of the two-dimensional electron solid at zero temperature are investigated. A self-consistent phonon theory is used and the cubic anharmonic correction coming from second order perturbation theory is included. This correction is larger than the self-consistent one, and yields a decrease in the phonon spectrum. Lindemann's ratio and corrections to the total energy of the solid are calculated as well.