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

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 نشر من قبل Ann K. Heilman
 تاريخ النشر 2000
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Y. Y. Xue




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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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