Origin of hysteresis and plateau-like behavior of the I-V characteristics of resonant tunneling diodes

In terms of numerical calculation of the coupled Wigner function-Poisson eq uations, the explanation to the origin of hysteresis and plateau-like behav ior of the I-V characteristics of double barrier resonant tunneling devices is put forth. Several basic physical factors play key roles in the process of electron tunneling. Among these the most important factors are the inte rference of the injected and the reflected electron waves which leads to th e formation of an emitter quantum well, the coupling between the energy lev el in the main quantum well and that in the emitter quantum well, and the c oupling between the energy level in the main quantum well and the conductio n band edge or the three-dimensional states in the emitter. The interplay o f these factors determines the form of the I-V curve of the resonant tunnel ing structure. The coupling between the energy levels in the emitter quantu m-well and the main quantum-well leads to the plateau behavior of the I-V c urves. The strength of the coupling determines the average slope of the pla teaulike region in the I-V curve. The bias domain that the coupling exists determines the length of the plateau-like structure in the I-V curve. The d omain can be controlled by adjusting the width of the barriers. The hystere sis is shown to be a manifestation of the above-mentioned energy level coup ling, the coupling between the energy level in the main quantum well and th e conduction band edge or the three-dimensional states in the emitter, and the quantitative accumulation and distribution of electrons in the emitter region. This work provides new insight for understanding the nonlinear I-V behavior and establishes a foundation for the future analysis of bistabilit y and oscillation behavior in resonant tunneling structures.