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Surface phase separation in nanosized charge-ordered manganites

S. Dong·F. Gao·Z. Q. Wang·J. -M. Liu·Z. F. Ren
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Abstract

Recent experiments showed that the robust charge-ordering in manganites can be weakened by reducing the grain size down to nanoscale. Weak ferromagnetism was evidenced in both nanoparticles and nanowires of charge-ordered manganites. To explain these observations, a phenomenological model based on surface phase separation is proposed. The relaxation of superexchange interaction on the surface layer allows formation of a ferromagnetic shell, whose thickness increases with decreasing grain size. Possible exchange bias and softening of the ferromagnetic transition in nanosized charge-ordered manganites are predicted.

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S. Dong, F. Gao, Z. Q. Wang, J. -M. Liu, Z. F. Ren. 2007-02-25. Surface phase separation in nanosized charge-ordered manganites. https://doi.org/10.1063/1.2709911

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