Theory of novel nonlinear quantum transport effects in resonant tunneling structures

The study of time-dependent, highly nonlinear, and nonequilibrium quantum-based device operation has been accomplished through the use of the quantum distribution function (QDF) in phase space. There are four important controversial issues on resonant tunneling structures (RTS) that have been resolved, resulting from the QDF simulations. These are: (a) the characteristic plateau-like structure, the presence of autonomous intrinsic high-frequency oscillations, current bistability, and hysteresis of the current voltage (I-V) curve; (b) the high-frequency small signal response when the RTS, biased in the negative differential resistance region, operates in the stable mode, and the role of the electron inertia at very high frequencies; (c) the binary information storage at zero bias, without energy dissipation, and the accompanying ‘anomalous’ current bistability phenomena in quantum well diodes with special source and/or drain structures; (d) the hysteresis of trapped hole charge in the barrier region and accompanying current bistability before the onset of the resonant-tunneling current peak in quantum-well diodes with type II band-edge alignment.