THEORY OF NOVEL NONLINEAR QUANTUM TRANSPORT EFFECTS IN RESONANT-TUNNELING STRUCTURES

The study of time-dependent, highly nonlinear, and nonequilibrium quan tum-based device operation has been accomplished through the use of th e quantum distribution function (QDF) in phase space. There are four i mportant controversial issues on resonant tunneling structures (RTS) t hat have been resolved, resulting from the QDF simulations. These are: (a) the characteristic plateau-like structure, the presence of autono mous intrinsic high-frequency oscillations, current bistability, and h ysteresis of the current voltage (I-V) curve; (b) the high-frequency s mall signal response when the RTS, biased in the negative differential resistance region, operates in the stable mode, and the role of the e lectron inertia at very high frequencies; (c) the binary information s torage 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-we ll diodes with type II band-edge alignment.