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Dielectrophoresis model for the colossal electroresistance of phase-separated manganites

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 نشر من قبل Shuai Dong
 تاريخ النشر 2007
  مجال البحث فيزياء
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We propose a dielectrophoresis model for phase-separated manganites. Without increase of the fraction of metallic phase, an insulator-metal transition occurs when a uniform electric field applied across the system exceeds a threshold value. Driven by the dielectrophoretic force, the metallic clusters reconfigure themselves into stripes along the direction of electric field, leading to the filamentous percolation. This process, which is time-dependent, irreversible and anisotropic, is a probable origin of the colossal electroresistance in manganites.



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