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Microstructure and magnetic properties in percolating (Ni–Fe)x(SiO2)1–x granular films

Published online by Cambridge University Press:  31 January 2011

Y. Xu  and
X. Yan
Y. Xu
Affiliation:
Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
X. Yan
Affiliation:
Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
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Abstract

We studied composition, structure, microstructure, and magnetic properties of percolating (Ni–Fe)x(SiO2)1−x granular thin films. We found that the magnetic susceptibility increases and the coercivity decreases when increasing x toward xt, the critical metallic volume fraction for the metal-insulator transition, and the susceptibility decreases and the coercivity increases when increasing annealing temperature for x just below xt. Comparison of the microstructure and the magnetic properties suggests that the enhanced magnetic susceptibility for x just below xt is probably associated with the labyrinthine structure of the granular magnetic particles where there is an enhanced surface-to-volume ratio of the magnetic particles.

Type
Articles
Information
Journal of Materials Research , Volume 11 , Issue 10 , October 1996 , pp. 2506 - 2517
Copyright
Copyright © Materials Research Society 1996

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