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arXiv · 1304.6512

Low temperature ferromagnetism, surface paramagnetism and exchange bias effect in nano-grained alpha-Fe1.4Ga0.6O3 oxide

R. N. Bhowmik·N. Naresh·B. Ghosh·S. Banerjee
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Abstract

The compound alpha-Fe1.4Ga0.6O3 has been prepared by mechanical alloying of alpha-Fe2O3 and Ga2O3 and subsequent heating of the mechanical alloyed samples in vacuum condition. Magnetic ordering of alpha-Fe2O3 has been modified by substitution of non-magnetic Ga atoms. The ferromagnetism in alpha-Fe1.4Ga0.6O3 is more soft and enhanced in comparison to alpha-Fe2O3. M\"ossbauer spectroscopy also confirmed enhanced ferromagnetic order in alpha-Fe1.4Ga0.6O3. The room temperature soft ferromagnetism by Ga substitution is interesting for designing alpha-Fe2O3 based unconventional ferromagnet, which is a great challenge to the materials scientists. The alpha-Fe1.4Ga0.6O3 samples also exhibited features of exchange bias, low temperature surface paramagnetism, and suppression of Morin transition. These features have been affected up to certain extent by the nano-sized grains of the samples.

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R. N. Bhowmik, N. Naresh, B. Ghosh, S. Banerjee. 2013-04-24. Low temperature ferromagnetism, surface paramagnetism and exchange bias effect in nano-grained alpha-Fe1.4Ga0.6O3 oxide. https://doi.org/10.1016/j.cap.2014.04.017

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