Investigations on resonant tunneling in III-V heterostructures: Comparison between experimental data and model calculations

Data obtained on a set of GaAs/AlGaAs double-barrier quantum-well resonant tunneling structures are compared with model calculations of the ideal case where scattering is negligible and tunneling is coherent throughout the entire structure. The comparison points to interface roughness in the well as the most likely cause for the observed large valley currents. The currents at low biases, before resonance sets in, are also studied. Their magnitude is found to be consistent also with the sequential tunneling picture.