Influence of interface structure on transversal electron transport

The influence of the sharpness of the interface on the electron transport is investigated. The simple one-dimensional tight-binding model, which allows the consideration of an interface with arbitrary sharpness, is examined. It is shown that an interface with size much larger than a(lambda/a)(1/3) (where a is the lattice constant and lambda is the electron wavelength) can be considered as smooth. This means that the interface transmittance for the electron crossing is of the order of unity. In the opposite limiting case of the sharp interface, the transmittance becomes suppressed as (a/lambda)(2). (C) 1998 Elsevier Science Ltd.