Coherent potential approximation as a voltage probe

Authors

Mikhail Ye Zhuravlev, University of Nebraska-LincolnFollow
A. V. Vedyayev, M. V. Lomonosov Moscow State University
Kirill D. Belashchenko, University of Nebraska-LincolnFollow
Evgeny Y. Tsymbal, University of Nebraska-LincolnFollow

Date of this Version

2012

Citation

PHYSICAL REVIEW B 85, 115134 (2012). DOI: 10.1103/PhysRevB.85.115134

Comments

Copyright © 2012 American Physical Society. Used by Permission.

Abstract

Coherent potential approximation (CPA) haswidely been used for studying the residual resistivity of bulk alloys and electrical conductivity in systems with structural disorder. Here, we revisit the single-site CPA within the Landauer-Büttiker approach applied to the electronic transport in layered structures and show that thismethod can be interpreted in terms of the B¨uttiker voltage-probe model that has been developed for treating phase-breaking scattering in mesoscopic systems. We demonstrate that the on-site vertex function, which appears within the single-site CPA formalism, plays the role of the local chemical potential within the voltage-probe approach. This interpretation allows the determination of the chemical potential profile across a disordered conductor, which is useful for analyzing results of transport calculations within the CPA. We illustrate this method by providing several examples. In particular, for layered systems with translational periodicity in the plane of the layers, we introduce the local resistivity and calculate the interface resistance between disordered layers.