Paramagnetic Spin Correlations in Colossal Magnetoresistive La0.7Ca0.3MnO3

Abstract

Neutron spectroscopy measurements reveal dynamic spin correlations throughout the Brillouin zone in the colossal magnetoresistive material La0.7Ca0.3MnO3 at 265 K (approximately 1.03 Tc). The long-wavelength behavior is consistent with spin diffusion, yet an additional and unexpected component of the scattering is also observed in low-energy constant-E measurements, which takes the form of ridges of strong quasielastic scattering running along (H 0 0) and equivalent directions. Well-defined Q-space correlations are observed in constant-E scans at energies up to at least 28 meV, suggesting robust short-range spin correlations in the paramagnetic phase.

v2: 5 pages, 5 figures. Figure added and text edited to match published version. v1: 5 pages, 4 figures

References in corpus (3)

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• Electronically smectic-like phase in a nearly half-doped manganite