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arXiv · 0905.3767

A phenomenological model for the pressure sensitivity of the Curie temperature in hole-doped manganites

G. Garbarino·C. Acha
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Abstract

We performed high pressure experiments on La(0.8)Ca(0.2-x)Sr(x)MnO(3) (LCSMO) (0 ) and the Curie temperature Tc of hole-doped manganites at a fixed doping level and for doping values below the 0.3 (Mn+4/Mn+3) ratio. By considering our results and collecting others from the literature, we were able to propose a phenomenological law that considers the systematic dependence of Tc with structural and electronic parameters. This law predicts fairly well the pressure sensitivity of Tc, its dependence with the A-cation radius disorder and its evolution in the high pressure range. Considering a Double Exchange model, modified by polaronic effects, the phenomenological law obtained for Tc can be associated with the product of two terms: the polaronic modified bandwidth and an effective hole doping.

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G. Garbarino, C. Acha. 2009-05-22. A phenomenological model for the pressure sensitivity of the Curie temperature in hole-doped manganites. https://doi.org/10.1209/0295-5075/88/46003

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