QUENCHING OF THE QUANTUM HALL-EFFECT IN A UNIFORM BALLISTIC QUANTUM-WIRE

Self-consistent calculations are made of wave functions and two kinds of Hall resistance for a 2DEG confined in a uniform ballistic quantum wire in a weak perpendicular magnetic field when several subbands are occupied. We find intermittent quenching of the Hall resistance associ ated with the local chemical potential as the electron density varies. The quenching is due to the overlap of opposite-going wave functions in the same subband, which is enhanced significantly by the singularit y of the density of states at the subband minimum as well as by Coulom b interactions between electrons.