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Liquid-like spatial distribution of magnetic polarons revealed by neutron scattering in La{1-x}Ca{x}MnO3

M. Hennion·F. Moussa·G. Biotteau·J. Rodriguez-Carvajal·L. Pinsard·A. Revcolevschi
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Abstract

Elastic neutron scattering experiments performed in semi-conducting La(1-x)Ca(x)MnO3 single crystals (x=0.05, 0.08), reveal new features in the problem of electronic phase separation and metal insulator transition. Below TN, the observation of a broad magnetic modulation in the q-dependent scattering intensity, centered at nearly identical qm whatever the q direction, can be explained by a liquid-like spatial distribution of similar magnetic droplets. A semi-quantitative description of their magnetic state, diameter, and average distance, can be done using a two-phase model. Such a picture can explain the anomalous characteristics of the spin wave branches and may result from unmixing forces between charge carriers predicted from the s-d model.

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M. Hennion, F. Moussa, G. Biotteau, J. Rodriguez-Carvajal, L. Pinsard, A. Revcolevschi. 1998-06-23. Liquid-like spatial distribution of magnetic polarons revealed by neutron scattering in La{1-x}Ca{x}MnO3. https://doi.org/10.1103/physrevlett.81.1957

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