Charge melting and polaron collapse in $La_{1.2}Sr_{1.8}Mn_{2}O_{7}$

L. Vasiliu-Doloc; S. Rosenkranz; R. Osborn; S. K. Sinha; J. W. Lynn; J. Mesot; O. H. Seeck; G. Preosti; A. J. Fedro; J. F. Mitchell

doi:10.1103/physrevlett.83.4393

arXiv · cond-mat/9907304

Charge melting and polaron collapse in $La_{1.2}Sr_{1.8}Mn_{2}O_{7}$

L. Vasiliu-Doloc·S. Rosenkranz·R. Osborn·S. K. Sinha·J. W. Lynn·J. Mesot·O. H. Seeck·G. Preosti·A. J. Fedro·J. F. Mitchell

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Abstract

X-ray and neutron scattering measurements directly demonstrate the existence of polarons in the paramagnetic phase of optimally-doped colossal magnetoresistive oxides. The polarons exhibit short-range correlations that grow with decreasing temperature, but disappear abruptly at the ferromagnetic transition because of the sudden charge delocalization. The "melting" of the charge ordering as we cool through $T_C$ occurs with the collapse of the quasi-static polaron scattering, and provides important new insights into the relation of polarons to colossal magnetoresistance.

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L. Vasiliu-Doloc, S. Rosenkranz, R. Osborn, S. K. Sinha, J. W. Lynn, J. Mesot, O. H. Seeck, G. Preosti, A. J. Fedro, J. F. Mitchell. 1999-07-20. Charge melting and polaron collapse in $La_{1.2}Sr_{1.8}Mn_{2}O_{7}$. https://doi.org/10.1103/physrevlett.83.4393

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