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Phase Competition in Ln0.5a0.5mno3 Perovskites

F. Rivadulla·E. Winkler·J. -S. Zhou·J. B. Goodenough
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Abstract

Single crystals of the systems Pr0.5(Ca1-xSrx)0.5MnO3, (Pr1-yYy)0.5(Ca1-xSrx)0.5MnO3, and Sm0.5Sr0.5MnO3 were grown to provide a series of samples with fixed ratio Mn(III)/Mn(IV)=1 having geometric tolerance factors that span the transition from localized to itinerant electronic behavior of the MnO3 array. A unique ferromagnetic phase appears at the critical tolerance factor tc= 0.975 that separates charge ordering and localized-electron behavior for t tc. This ferromagnetic phase, which has to be distinguished from the ferromagnetic metallic phase stabilized at tolerance factors t>tc, separates two distinguishable Type-CE antiferromagnetic phases that are metamagnetic. Measurements of the transport properties under hydrostatic pressure were carried out on a compositions t a little below tc in order to compare the effects of chemical vs. hydrostatic pressure on the phases that compete with one another near t=tc.

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F. Rivadulla, E. Winkler, J. -S. Zhou, J. B. Goodenough. 2002-09-16. Phase Competition in Ln0.5a0.5mno3 Perovskites. https://doi.org/10.1103/physrevb.66.174432

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