High performance resonant tunnelling structures on GaAs substrates

Abstract

GaAs-based resonant tunnelling structures of high quality were grown by molecular beam epitaxy. Room temperature peak-to-valley ratios of 4.8 for a GaAs/AlGaAs double barrier quantum well, 4.1 for GaAs/AlGaAs with InGaAs quantum well and 5.9 for GaAs/AlGaAs with adjacent InGaAs ‘prewell’ were obtained, in connection with reasonable peak current densities.