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Impact of Charge Ordering on Magnetic Correlations in Perovskite (Bi,Ca)MnO_3

Wei Bao·J. D. Axe·C. H. Chen·S-W. Cheong
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Abstract

Single crystalline (Bi,Ca)MnO3 (74< %Ca <82) were studied with neutron scattering, electron diffraction and bulk magnetic measurement. We discovered dynamic ferromagnetic spin correlations at high temperatures, which are replaced by antiferromagnetic spin fluctuations at a concomitant charge ordering and structural transition. Our results indicate that thermal-activated hopping of the Jahn-Teller active e_g electrons in these insulating materials, nevertheless, induce ferromagnetic interaction through double-exchange mechanism. It is the ordering of these charges competing with the double-exchange ferromagnetic metallic state.

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Wei Bao, J. D. Axe, C. H. Chen, S-W. Cheong. 1996-11-13. Impact of Charge Ordering on Magnetic Correlations in Perovskite (Bi,Ca)MnO_3. https://doi.org/10.1103/physrevlett.78.543

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