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arXiv · 0705.3296

Dielectrophoresis model for the colossal electroresistance of phase-separated manganites

Shuai Dong·Han Zhu·J. -M. Liu
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Abstract

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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Shuai Dong, Han Zhu, J. -M. Liu. 2007-09-01. Dielectrophoresis model for the colossal electroresistance of phase-separated manganites. https://doi.org/10.1103/physrevb.76.132409

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