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arXiv · 1805.05172

Study of the ferromagnetic-insulator phase in manganites

Sanjukta Paul·Sudhakar Yarlagadda
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Abstract

Understanding the coexistence of ferromagnetism and insulating behavior in manganites is an unsolved problem. We propose a localized-band model involving effective intermediate-range electron-electron (electron-hole) repulsion (attraction) generated by cooperative electron-phonon interaction. Double exchange mechanism, involving holes virtually hopping to nearest neighbors and back, produces magnetic polarons in an antiferromagnetic environment; when these magnetic polarons coalesce and percolate the system, we get a ferromagnetic insulator. Ferromagnetism gets more pronounced when the holes (doping) increases or when the ratio hopping/polaronic-energy dominates over superexchange-coupling/hopping.

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Sanjukta Paul, Sudhakar Yarlagadda. 2018-05-14. Study of the ferromagnetic-insulator phase in manganites. https://arxiv.org/abs/1805.05172

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