Sequential tunneling due to intersubband scattering in double-barrier resonant tunneling devices

Abstract

Magnetoquantum oscillations in the tunnel current of double-barrier n-GaAs/(AlGa)As/GaAs/(AlGa)As/GaAs resonant tunneling devices reveal evidence of sequential tunneling in the voltage range corresponding to the resonance when electrons tunnel into the second subband of the GaAs quantum well. The sequential tunneling arises from intersubband scattering between two quasi-bound states of the well. Near this resonance, the charge buildup in the well can be estimated from the magnetoquantum oscillations.