Charge Density Wave State of Two-Dimensional Electrons in Strong Magnetic Fields

Abstract

Charge density wave (CDW) states of a two-dimensional electron system occupying only the lowest Landau subband are investigated at T =0 by the Hartree-Fock approximation. It is shown that even in the high density region the CDW state has the same periodicity as that of a Wigner lattice but has considerable overlaps of wave functions of nearby electrons. Hence the Wigner lattice at low density changes smoothly to the CDW state at higher density. This coincidence of the periodicity of the CDW with that of the Wigner lattice results from the appearance of a large gap at the Fermi level in the energy spectrum.