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arXiv · 1202.0487

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

Joel S. Helton·Matthew B. Stone·Dmitry A. Shulyatev·Yakov M. Mukovskii·Jeffrey W. Lynn
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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.

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Joel S. Helton, Matthew B. Stone, Dmitry A. Shulyatev, Yakov M. Mukovskii, Jeffrey W. Lynn. 2012-02-02. Paramagnetic Spin Correlations in Colossal Magnetoresistive La0.7Ca0.3MnO3. https://doi.org/10.1103/physrevb.85.144401

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