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arXiv · 0801.4626

Limited local electron-lattice coupling in manganites

D. Sanchez·M. J. Calderon·J. Sanchez-Benitez·A. J. Williams·J. P. Attfield·P. A. Midgley·N. D. Mathur
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Abstract

(Pr,Ca)MnO3 is the archetypal charge-ordered manganite, but in Pr0.48Ca0.52MnO3 we find (using convergent-beam electron diffraction and dark-field images) that the superlattice period is locally incommensurate with respect to the parent lattice, and that the superlattice orientation possesses significant local variations. This suggests that local electron-lattice coupling never overwhelmingly dominates the rich physics of manganites, even in the most extreme scenarios that produce the largest colossal magnetoresistance effects.

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D. Sanchez, M. J. Calderon, J. Sanchez-Benitez, A. J. Williams, J. P. Attfield, P. A. Midgley, N. D. Mathur. 2008-01-30. Limited local electron-lattice coupling in manganites. https://doi.org/10.1103/physrevb.77.092411

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