Intrinsic Nanoscale Inhomogeneities in Transition Metal Oxides

TL;DR

This paper investigates nanoscale inhomogeneities in transition metal oxides, revealing static and dynamic polaron correlations near the Curie temperature, indicating a glass-like state with implications for understanding complex oxide behaviors.

Contribution

It provides new insights into the temperature-dependent static and dynamic polaron correlations in La0.7Ca0.3MnO3 using advanced scattering techniques, highlighting a glass-like state.

Findings

Nanoscale static polaron correlations develop near the Curie temperature.

A glass-like state of short-range correlations is observed.

Dynamic correlations persist above a certain temperature T*.

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.