Self-consistent calculation of resonant tunneling in asymmetric double barriers in a magnetic field

We have studied resonant tunneling through an asymmetric double barrier in the presence of a magnetic field in the direction of the current flow. The electron-electron interaction as well as coupling to a longitudinal-optical phonon field are included. The main resonance peak in the I-V characteristic is followed by a phonon-induced peak, both showing a structure at finite magnetic field. We find a bistable region whose width oscillates with magnetic field, in accordance with experiment. This region is expected in the main resonance, yet, as we show, it may also be present in the phonon peak in the limit of large asymmetry. {} 1996 The American Physical Society.