Exchange Interaction in the Co-SiO₂ Nanocomposite Films

Abstract:

The properties of Co-SiO2 nanogranular composite films, containing a Co volume fraction ranging from 0.3 to 0.8, have been characterized by means of magnetic measurements, NMR study, and ferromagnetic resonance. Thermal decrease of CoX(SiO2)100-X magnetization follows the T3/2 law and allows to estimate the exchange interaction constant A. With growing nominal Co content the transitions from granular to continuous structural state at 36% Co are registered by FMR measurements. The spectrum of standing spin-wave has been detected in the perpendicular experiment configuration for films with the Co content above 52 vol. %. It is found that the type of the dispersion relation of spin waves in Co-SiO2 composite films is affected by the exchange coupling fluctuations.

• Periodical: Solid State Phenomena (Volumes 168-169)
• Pages: 265-268
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.168-169.265
• Online since: December 2010
• Authors: Elena A. Denisova, Rauf S. Iskhakov, S.V. Stolyar, S.V. Komogortsev, L.A. Chekanova, V.K. Maltsev, Y. Kalinin, A.V. Sitnikov
• Keywords: Exchange Coupling Parameter, Ferromagnetic Resonance (FMR), Granular Composite Films

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