Quantum Size Effect in Conductivity of Multilayer Metal Films

TL;DR

This paper predicts three types of quantum size effects in the conductivity of multilayer metal films, highlighting a unique resonance phenomenon influenced by interface positioning and scattering mechanisms.

Contribution

It introduces a new type of quantum size effect specific to multilayer films with rough interfaces, detailing conditions for geometric resonances and their dependence on interface properties.

Findings

Three quantum size effects in conductivity are predicted.

A unique geometric resonance occurs at specific interface positions.

Resonance features depend on interface potential and barrier width.

Abstract

Conductivity of quantized multilayer metal films is analyzed with an emphasis on scattering by rough interlayer interfaces. Three different types of quantum size effect (QSE) in conductivity are predicted. Two of these QSE are similar to those in films with scattering by rough walls. The third type of QSE is unique and is observed only for certain positions of the interface. The corresponding peaks in conductivity are very narrow and high with a finite cutoff which is due only to some other scattering mechanism or the smearing of the interface. There are two classes of these geometric resonances. Some of the resonance positions of the interface are universal and do not depend on the strength of the interface potential while the others are sensitive to this potential. This geometric QSE gradually disappears with an increase in the width of the interlayer potential barrier.