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Intrinsic Nanoscale Inhomogeneities in Transition Metal Oxides

J. W. Lynn·D. N Argyriou·Y. Ren·Y. Chen·Y. M. Mukovskii·D. A. Shulyatev
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Abstract

Neutron elastic, inelastic and high energy x-ray scattering techniques are used to explore the nature of the polaron order and dynamics in La0.7Ca0.3MnO3. Static polaron correlations develop within a narrow temperature regime as the Curie temperature is approached from low temperatures, with a nanoscale correlation length that is only weakly temperature dependent. The static nature of these short-range polaron correlations indicates the presence of a glass-like state, similar to the observations for the bilayer manganite in the metallic-ferromagnetic doping region. In addition to this elastic component, inelastic scattering measurements reveal dynamic correlations with a comparable correlation length, and with an energy distribution that is quasielastic. The elastic component disappears at a higher temperature T*, above which the correlations are purely dynamic. The overall behavior bears a remarkable resemblance to the magnetic fluctuation spectrum recently observed in underdoped cuprates.

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J. W. Lynn, D. N Argyriou, Y. Ren, Y. Chen, Y. M. Mukovskii, D. A. Shulyatev. 2006-12-29. Intrinsic Nanoscale Inhomogeneities in Transition Metal Oxides. https://arxiv.org/abs/cond-mat/0701001

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