Oscillatory Interlayer Exchange Coupling and Its Temperature Dependence in [Pt/Co]₃/NiO/[Co/Pt]₃ Multilayers with Perpendicular Anisotropy

Authors

Z. Y. Liu, University of Nebraska-Lincoln
Shireen Adenwalla, University of Nebraska-LincolnFollow

Date of this Version

July 2003

Comments

Published in Physical Review Letters 91, 037207 (2003).
URL: http://link.aps.org/abstract/PRL/v91/e037207
doi:10.1103/PhysRevLett.91.037207
Copyright 2003 American Physical Society. Used by permission.

Abstract

Interlayer exchange coupling that oscillates between antiferromagnetic and ferromagnetic as a function of NiO thickness has been observed in [Pt(5 Å)/Co(4 Å)]₃/NiO(t_NiO Å)/[Co(4 Å)/Pt(5 Å)]₃ multilayers with out-of-plane anisotropy. The period of oscillation corresponds to ~2 monolayers of NiO. This oscillatory behavior is possibly attributed to the antiferromagnetic ordering in NiO. The antiferromagnetic interlayer exchange coupling for the 11 Å NiO layer shows an increase in coupling strength with increasing temperature, in agreement with the quantum interference model of Bruno for insulating spacer layers. A coexistence of exchange biasing and antiferromagnetic interlayer exchange coupling has been observed below T = 250 K.