SELF-CONSISTENT SIMULATION OF QUANTUM WIRES IN PERIODIC HETEROJUNCTION STRUCTURES

We simulate the low temperature confinement of electrons in quantum wires formed at the comers of periodic saw-tooth structures consisting of layers of AlxGa1-xAs and GaAs materials. A very efficient self-consistent procedure for the solution of Schrodinger's and Poisson's equations, including shifted periodic boundary conditions, is used to obtain the wave functions and energy levels in the quantum well. Self-consistency is very important to obtain an accurate result; in particular, the precise details of the potential at the comers must be resolved. The formation of a quantum wire at the comers of the GaAs layer is found to be very sensitive to the physical parameters of the neighboring AlxGa1-xAs layers. We find that to avoid sizeable electron population in the GaAs region between the comers, asymmetric doping is necessary, which normally results in electron confinement only at every other comer.