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arXiv · 1112.1927

Pressure induced magnetic phase separation in La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ manganite

M. Baldini·L. Capogna·M. Capone·E. Arcangeletti·C. Petrillo·I. Goncharenko·P. Postorino
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Abstract

The pressure dependence of the Curie temperature T$_{C}(P)$ in La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ was determined by neutron diffraction up to 8 GPa, and compared with the metallization temperature T$_{IM}(P)$ \cite{irprl}. The behavior of the two temperatures appears similar over the whole pressure range suggesting a key role of magnetic double exchange also in the pressure regime where the superexchange interaction is dominant. Coexistence of antiferromagnetic and ferromagnetic peaks at high pressure and low temperature indicates a phase separated regime which is well reproduced with a dynamical mean-field calculation for a simplified model. A new P-T phase diagram has been proposed on the basis of the whole set of experimental data.

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M. Baldini, L. Capogna, M. Capone, E. Arcangeletti, C. Petrillo, I. Goncharenko, P. Postorino. 2011-12-08. Pressure induced magnetic phase separation in La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ manganite. https://doi.org/10.1088/0953-8984%2F24%2F4%2F045601

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