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Insulator-metal transition shift related to magnetic polarons in La0.67-xYxCa0.33MnO3

G. Li·S. -J. Feng·F. Liu·Y. Yang·R. -K. Zheng·T. Qian·X. -Y. Guo·X. -G. Li
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Abstract

The magnetic transport properties have been measured for La0.67-xYxCa0.33MnO3 (0 <= x <= 0.14) system. It was found that the transition temperature Tp almost linearly moves to higher temperature as H increases. Electron spin resonance confirms that above Tp, there exist ferromagnetic clusters. From the magnetic polaron point of view, the shift of Tp vs. H was understood, and it was estimated that the size of the magnetic polaron is of 9.7~15.4 angstrom which is consistent with the magnetic correlation length revealed by the small-angle neutron-scattering technique. The transport properties at temperatures higher than Tp conform to the variable-range hopping mechanism.

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G. Li, S. -J. Feng, F. Liu, Y. Yang, R. -K. Zheng, T. Qian, X. -Y. Guo, X. -G. Li. 2003-01-16. Insulator-metal transition shift related to magnetic polarons in La0.67-xYxCa0.33MnO3. https://doi.org/10.1140/epjb%2Fe2003-00068-8

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