One-dimensional subbands of narrow electron channels in gated AlxGa1−xAs/GaAs heterojunctions

Abstract

Lateral quantization of the electronic motion in ${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As/GaAs heterojunctions with a microstructured gate electrode is investigated with static magnetotransport and infrared spectroscopy. In these structures a negative gate bias causes a transition from two-dimensional to quasi-one-dimensional electronic behavior. Spacings of one-dimensional subbands as well as one-dimensional electron densities are derived from quantum oscillations of the magnetoresistance and compared with intersubband resonance energies and electron densities extracted from infrared spectra.