Valley splitting control in SiO2/Si/SiO2 quantum wells in the quantum Hall regime

摘要: SiO 2 /Si/SiO quantum wells fabricated on SIMOX silicon-on-insulator substrates are examined in the quantized Hall regime. An 8 nm well behaves as a single layer of two-dimensional electrons at accessible gate voltages. By using front and back gates, wave function confinement direction can be shifted continuously between two /Si interfaces formed through different processes. We find that this results continuous evolution valley splitting which is asymmetric with electrical bias. Wider show bilayer behavior where each layer, demonstrating its control shown by arises due to properties interfaces. Estimates made Landau level coincidences activation energies. The coincidence levels opposite spin, valley, like cyclotron indices ν=6 shows anticrossing behavior.