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Competition of charge, orbital, and ferromagnetic correlations in layered manganites

D. B. Romero·Y. Moritomo·J. F. Mitchell·H. D. Drew
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Abstract

The competition of charge, orbital, and ferromagnetic interactions in layered manganites is investigated by magneto-Raman scattering spectroscopy. We find that the colossal magnetoresistance effect in the layered compounds results from the interplay of the orbital and ferromagnetic double-exchange correlations. Inelastic scattering by charge-order fluctuations dominates the quasiparticle dynamics in the ferromagnetic-metal state. The scattering is suppressed at low frequencies, consistent with the opening of a charge-density wave pseudogap.

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D. B. Romero, Y. Moritomo, J. F. Mitchell, H. D. Drew. 2000-07-05. Competition of charge, orbital, and ferromagnetic correlations in layered manganites. https://doi.org/10.1103/physrevb.63.132404

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