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Title: Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies

Abstract

Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies separated by a non-magnetic spacer is studied using ferromagnetic resonance. The samples consist of a Co/Ni multilayer with perpendicular magnetic anisotropy and a CoFeB layer with easy-plane anisotropy separated by a variable thickness Ru layer. At a fixed frequency, we show that there is an avoided crossing of layer ferromagnetic resonance modes providing direct evidence for interlayer coupling. The mode dispersions for different Ru thicknesses are fit to a Heisenberg-type model to determine the interlayer exchange coupling strength and layer properties. The resulting interlayer exchange coupling varies continuously from antiferromagnetic to ferromagnetic as a function of the Ru interlayer thickness. These results show that the magnetic layer single domain ground state consists of magnetizations that can be significantly canted with respect to the layer planes and the canting can be tuned by varying the Ru thickness and the layer magnetic characteristics, a capability of interest for applications in spin-transfer torque devices.

Authors:
 [1];  [2]; ;  [1]; ;  [3];  [4]
  1. Department of Physics, New York University, New York, New York 10003 (United States)
  2. (Spain)
  3. Spin Transfer Technologies, Inc., Fremont, California 94538 (United States)
  4. CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian (Spain)
Publication Date:
OSTI Identifier:
22590524
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; ANTIFERROMAGNETISM; DISPERSIONS; EQUIPMENT; FERROMAGNETIC RESONANCE; GROUND STATES; LAYERS; MAGNETIZATION; SPIN; THICKNESS

Citation Formats

Fallarino, Lorenzo, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian, Sluka, Volker, Kent, Andrew D., Kardasz, Bartek, Pinarbasi, Mustafa, and Berger, Andreas. Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies. United States: N. p., 2016. Web. doi:10.1063/1.4960795.
Fallarino, Lorenzo, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian, Sluka, Volker, Kent, Andrew D., Kardasz, Bartek, Pinarbasi, Mustafa, & Berger, Andreas. Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies. United States. doi:10.1063/1.4960795.
Fallarino, Lorenzo, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian, Sluka, Volker, Kent, Andrew D., Kardasz, Bartek, Pinarbasi, Mustafa, and Berger, Andreas. 2016. "Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies". United States. doi:10.1063/1.4960795.
@article{osti_22590524,
title = {Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies},
author = {Fallarino, Lorenzo and CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian and Sluka, Volker and Kent, Andrew D. and Kardasz, Bartek and Pinarbasi, Mustafa and Berger, Andreas},
abstractNote = {Interlayer exchange coupling between layers with perpendicular and easy-plane magnetic anisotropies separated by a non-magnetic spacer is studied using ferromagnetic resonance. The samples consist of a Co/Ni multilayer with perpendicular magnetic anisotropy and a CoFeB layer with easy-plane anisotropy separated by a variable thickness Ru layer. At a fixed frequency, we show that there is an avoided crossing of layer ferromagnetic resonance modes providing direct evidence for interlayer coupling. The mode dispersions for different Ru thicknesses are fit to a Heisenberg-type model to determine the interlayer exchange coupling strength and layer properties. The resulting interlayer exchange coupling varies continuously from antiferromagnetic to ferromagnetic as a function of the Ru interlayer thickness. These results show that the magnetic layer single domain ground state consists of magnetizations that can be significantly canted with respect to the layer planes and the canting can be tuned by varying the Ru thickness and the layer magnetic characteristics, a capability of interest for applications in spin-transfer torque devices.},
doi = {10.1063/1.4960795},
journal = {Applied Physics Letters},
number = 8,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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