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arXiv · 1502.05847

Magnetic dilution on LaCrO$_3$

Romualdo S. Silva Jr.·Petrucio Barrozo·N. O. Moreno·J. Albino Aguiar
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Abstract

In this work, we study the effect of the magnetic dilution of Cr$^{3+}$ on the LaCrO$_3$ half doped with Al. Pure and half-doped samples were prepared by combustion method using urea as fuel. The crystal structure was investigated by X-ray diffraction. Rietveld analysis reveal a structural phase transition caused by the increase of the chemical pressure due difference of Al$^{3+}$ and Cr$^{3+}$ ionic radii. SEM images shows that the samples exhibit a spherical formation and irregular morphologies. Magnetization measurements as a function of temperature reveal an antiferromagnetic order in both samples with a large decrease of T$_N$ (N\'eel temperature) with Al doping. The reduction of frustration factor and the increase of the magnetic moment of the doped sample could be attributed to the breaking of the long-range antiferromagnetic order. The magnetic hysteresis loops show a typical antiferromagnetic behavior with a slightly spin canting for the doped sample.

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Romualdo S. Silva Jr., Petrucio Barrozo, N. O. Moreno, J. Albino Aguiar. 2015-02-20. Magnetic dilution on LaCrO$_3$. https://arxiv.org/abs/1502.05847

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