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Glass Transition in the Polaron Dynamics of CMR Manganites

D. N. Argyriou·J. W. Lynn·R. Osborn·B. Campbell·J. F. Mitchell·U. Ruett·H. N. Bordallo·A. Wildes·C. D. Ling
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Abstract

Neutron scattering measurements on a bilayer manganite near optimal doping show that the short-range polarons correlations are completely dynamic at high T, but then freeze upon cooling to a temperature T* 310 K. This glass transition suggests that the paramagnetic/insulating state arises from an inherent orbital frustration that inhibits the formation of a long range orbital- and charge-ordered state. Upon further cooling into the ferromagnetic-metallic state (Tc=114 K), where the polarons melt, the diffuse scattering quickly develops into a propagating, transverse optic phonon.

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D. N. Argyriou, J. W. Lynn, R. Osborn, B. Campbell, J. F. Mitchell, U. Ruett, H. N. Bordallo, A. Wildes, C. D. Ling. 2002-05-08. Glass Transition in the Polaron Dynamics of CMR Manganites. https://doi.org/10.1103/physrevlett.89.036401

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