Electric-field effect on the transmittivity of aperiodic Kronig-Penney crystals

We describe the effect of a static and uniform electric field on the electronic transport properties of one-dimensional periodic and deterministic aperiodic systems described by the Kronig-Penney model. We study the crystal transmittivity as a function of the length of the sample and of the field strength. In the periodic case we interpret the results exploiting the tilted band scheme and point out regions with a more than exponential decreasing rate of transmittivity. In the case of an incommensurate slowly varying potential we interpret the fine structure of the transmittivity by means-of a continuous approximation. In the pseudorandom case we confirm the delocalization effect of the field and we compare the results with the purely random case.