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arXiv · 1007.1943

AC Susceptibility Studies in Fe doped La0.65Ca0.35Mn1-xFexO3: Rare Earth Manganites

Wiqar Hussain Shah·S. K. Hasanain
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Abstract

The effect of Fe substitution on Mn sites in the colossal magnetoresistive compounds La0.65Ca0.35Mn1-xFexO3 with 0.01 0.04 Fe concentration. With increasing Fe concentration the x" peak shift to T<T1/2 (mid point of the transition temperature) and becomes broader. The x" peak moves to 8 or 10 K higher temperature on the application of a dc field, for 3 & 4% samples. We also see increasing low temperature dissipation in more strongly Fe doped samples i.e. increasing the Fe, leads to increased spin disorder and dissipation at low temperature. The effect of the dc field is discussed in terms of the suppression of spin fluctuations close to Tc. The same ionic radii of Fe3+ and Mn3+ cause no structure changes in either series, yet ferromagnetism has been consistently suppressed by Fe doping. Doping with Fe bypasses the usually dominant lattice effects, but depopulate the hopping electrons and thus weakens the double exchange. The results were explained in terms of the formation of magnetic clusters of Fe ions.

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Wiqar Hussain Shah, S. K. Hasanain. 2010-07-12. AC Susceptibility Studies in Fe doped La0.65Ca0.35Mn1-xFexO3: Rare Earth Manganites. https://arxiv.org/abs/1007.1943

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