Abstract
The resistance of planar barriers is discussed for a variety of situations in which different sources of scattering act incoherently, allowing a semiclassical approach. This includes single barriers, a sequence of identical parallel barriers, and identical barriers at random angles simulating grain boundaries. Existing results are related, and only limited extension of these is provided. The case of a single barrier embedded in a uniformly resistive medium has been treated by Kunze and others. Kunze's analysis is validated and interpreted via a considerably simplified version of his model. © 1995 The American Physical Society.