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Field-Induced Crossover and Colossal Magnetoresistance in La(0.7)Pb(0.3)MnO(3)

Y. Y. Xue·B. Lorenz·A. K. Heilman·M. Gospodinov·S. G. Dobreva·C. W. Chu
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Abstract

A field-induced crossover is observed in the resistivity and magnetization (M) of a La(0.7)Pb(0.3)MnO(3) single crystal. The field-dependence of the resistivity and M suggests that a small spin-canted species with mean-field-like interactions dominates at low fields (H), whereas, individual spins and 3D Ising/Heisenberg models describe the high-H behavior rather well. Around the ferromagnetic transition, an H-induced destruction of the small spin-canted magnetic polarons is accompanied by large magnetoresistance.

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Y. Y. Xue, B. Lorenz, A. K. Heilman, M. Gospodinov, S. G. Dobreva, C. W. Chu. 2000-04-20. Field-Induced Crossover and Colossal Magnetoresistance in La(0.7)Pb(0.3)MnO(3). https://arxiv.org/abs/cond-mat/0002468

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