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Radio Frequency Magnetron Sputtering of GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates
Published on: April 12, 2019
Dominant dipolar interaction and glassy magnetic behaviour in polymer-coated magnetite nanoparticles
M Thakur1, M Pal Chowdhury, S Majumdar
1Department of Solid State Physics and Center for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India.
Abstract:
The static and dynamic properties of magnetization have been investigated for polymer-coated magnetite nanoparticles with sizes from 5 to 15 nm. The analysis of the temperature dependence of zero-field-cooled magnetization indicates that the effective anisotropy constant is found to increase with the decrease of particle size, which is ascribed to the increase of surface anisotropy. The relaxation of the remanent magnetization clearly shows the signature of dominant dipolar interparticle interaction. The dynamics of magnetization also indicates the signature of glassy magnetic behaviour. The memory effect in the temperature dependence of field-cooled magnetization is noticed, which is inconsistent with the glassy magnetic behaviour.
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