Resonant Magnetotunneling in AlGaAs/GaAs Triple Barrier Diodes

Abstract

Resonant magnetotunneling in a triple barrier diode, where two quantum wells are formed by three barriers, is studied by applying magnetic fields both perpendicular and parallel to the interfaces. Under the perpendicular magnetic field, an oscillatory structure is found in the current-voltage characteristics ( I - V 's) in addition to the large peaks which have been found without magnetic field. The period of the oscillation is proportional to the magnetic field. The structure is attributed to inelastic tunnelings with an LO-phonon emission and subsequent change in the Landau quantum number. Under the parallel magnetic field, strong broadening of the large peaks towards a larger bias is found. A model for the broadening is proposed.