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Title: Interfacial and surface magnetism in epitaxial NiCo2O4(001)/MgAl2O4 films
NiCo2O4 (NCO) films grown on MgAl2O4 (001) substrates have been studied using magnetometry and x-ray magnetic circular dichroism based on x-ray absorption spectroscopy and spin-polarized inverse photoemission spectroscopy with various thicknesses down to 1.6 nm. The magnetic behavior can be understood in terms of a layer of optimal NCO and an interfacial layer (1.2 ± 0.1 nm), with a small canting of magnetization at the surface. The thickness dependence of the optimal layer can be described by the finite-scaling theory with a critical exponent consistent with the high perpendicular magnetic anisotropy. The interfacial layer couples antiferromagnetically to the optimal layer, generating exchange-spring styled magnetic hysteresis in the thinnest films. The non-optimal and measurement-speed-dependent magnetic properties of the interfacial layer suggest substantial interfacial diffusion.  more » « less
Award ID(s):
2044049
PAR ID:
10496204
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Journal of Applied Physics
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
133
Issue:
19
ISSN:
0021-8979
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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