QUANTUM-WELL, VOLTAGE-INDUCED QUANTUM-WELL, AND QUANTUM BARRIER ELECTRON WAVE-GUIDES - MODE CHARACTERISTICS AND MAXIMUM CURRENT

It is shown that finite-potential heterostructure wells, homostructure voltage-induced wells, and heterostructure barriers can act as waveguides for ballistic electrons and that waveguiding is described by a single dispersion relation and can occur at energies above all band edges. The guided mode cutoffs, electron velocity, effective mass, density of states, and ballistic current density (applicable to 2D electron gases) are presented. The maximum ballistic guided current flowing in a given direction for a 10 monolayer Ga0.75Al0.25As/GaAs/Ga0.9Al0.1As waveguide is found to be 2.3 mA per mu-m of waveguide width-allowing considerably greater currents than in single-mode quantum wires.