0 Competition of charge , orbital , and ferromagnetic correlations in layered manganites
نویسندگان
چکیده
The competition of charge, orbital, and ferromagnetic interactions in lay-ered 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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