Exchange Model for Oscillatory Interlayer Coupling and Induced Unidirectional Anisotropy in [Pt/Co]₃/NiO/[Pt/Co]₃ Multilayers

Authors

Mikhail Ye Zhuravlev, University of Nebraska-LincolnFollow
Evgeny Y. Tsymbal, University of Nebraska-LincolnFollow
Sitaram Jaswal, University of NebraskaFollow

Date of this Version

5-28-2004

Comments

Published in Physical Review Letters 92, 219703 (2004).
URL: http://link.aps.org/abstract/PRL/v92/e219703
doi:10.1103/PhysRevLett.92.219703
Copyright 2004 American Physical Society. Used by permission.

Abstract

In a recent Letter [1] Liu and Adenwalla found an interesting oscillatory behavior of the interlayer exchange coupling (IEC) through an insulating NiO (111) layer with a period of 2 monolayers (ML). They interpreted this phenomenon in terms of multiple reflections of electronic waves from a periodic atomic potential in the spirit of the model of Ref. [2]. However, this interpretation is not consistent with the tunneling mechanism used by the authors which would result in a modulated exponential decrease of the IEC but no periodic change in sign. In this Comment we show that the observed oscillatory IEC can be explained quantitatively by the exchange interaction at the interfaces and in the bulk of the antiferromagnetic NiO film.