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Title: Magnetic properties and interlayer coupling of epitaxial Co/Cu films on Si

Abstract

Thin films of Co and Co/Cu/Co trilayers with wedged Cu interlayers were grown epitaxially on Cu buffer layers on hydrogen passivated Si(001) wafers. We find that single Co layers have a well-defined four-fold anisotropy but with smaller in-plane anisotropies than observed in Co grown on Cu crystals. Ruderman–Kittel–Kasuya–Yosida (RKKY) interlayer coupling is observed in one Co/Cu/Co sample which is the smoothest of the films as measured by atomic force microscopy. Some of the films also form a dot-like structure on the surface. Intermixing at elevated temperatures between the Cu buffer and Si limits the ability to form flat surfaces to promote RKKY coupling.

Authors:
; ; ; ; ;  [1]
  1. Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)
Publication Date:
OSTI Identifier:
22314614
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; ATOMIC FORCE MICROSCOPY; CRYSTALS; EPITAXY; HYDROGEN; LAYERS; MAGNETIC PROPERTIES; SURFACES; THIN FILMS

Citation Formats

Mansell, R., Petit, D. C. M. C., Fernández-Pacheco, A., Lavrijsen, R., Lee, J. H., and Cowburn, R. P. Magnetic properties and interlayer coupling of epitaxial Co/Cu films on Si. United States: N. p., 2014. Web. doi:10.1063/1.4893306.
Mansell, R., Petit, D. C. M. C., Fernández-Pacheco, A., Lavrijsen, R., Lee, J. H., & Cowburn, R. P. Magnetic properties and interlayer coupling of epitaxial Co/Cu films on Si. United States. doi:10.1063/1.4893306.
Mansell, R., Petit, D. C. M. C., Fernández-Pacheco, A., Lavrijsen, R., Lee, J. H., and Cowburn, R. P. Thu . "Magnetic properties and interlayer coupling of epitaxial Co/Cu films on Si". United States. doi:10.1063/1.4893306.
@article{osti_22314614,
title = {Magnetic properties and interlayer coupling of epitaxial Co/Cu films on Si},
author = {Mansell, R. and Petit, D. C. M. C. and Fernández-Pacheco, A. and Lavrijsen, R. and Lee, J. H. and Cowburn, R. P.},
abstractNote = {Thin films of Co and Co/Cu/Co trilayers with wedged Cu interlayers were grown epitaxially on Cu buffer layers on hydrogen passivated Si(001) wafers. We find that single Co layers have a well-defined four-fold anisotropy but with smaller in-plane anisotropies than observed in Co grown on Cu crystals. Ruderman–Kittel–Kasuya–Yosida (RKKY) interlayer coupling is observed in one Co/Cu/Co sample which is the smoothest of the films as measured by atomic force microscopy. Some of the films also form a dot-like structure on the surface. Intermixing at elevated temperatures between the Cu buffer and Si limits the ability to form flat surfaces to promote RKKY coupling.},
doi = {10.1063/1.4893306},
journal = {Journal of Applied Physics},
number = 6,
volume = 116,
place = {United States},
year = {Thu Aug 14 00:00:00 EDT 2014},
month = {Thu Aug 14 00:00:00 EDT 2014}
}
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  • No abstract prepared.
  • Co/Cu/Co sandwiches were grown by molecular beam epitaxy onto a Cu(100) crystal with the intervening Cu layer fabricated to be wedge shaped. Electron diffraction was used to monitor the layer-by-layer growth. Films with 8, 14, and 20 monolayer- (ML) thick Co layers were investigated {ital in} {ital situ} by means of the magneto-optic Kerr effect. Characteristic hysteresis loops along the wedges, as a function of Cu thickness, unambiguously identify the oscillatory behavior in the sign of the exchange coupling between the two Co films. The oscillation periodicity (5.5 ML's of Cu) and, most importantly, the coupling strength are shown tomore » be independent of the Co-layer thickness.« less