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arXiv · 0801.2054

Conductance Switching and Inhomogeneous Field Melting in the Charge Ordered Manganites

Anamitra Mukherjee·Kalpataru Pradhan·Pinaki Majumdar
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Abstract

The field induced switching of conductance in the charge ordered half-doped manganites is controlled by the combination of metastability, an inhomogeneous high field state, and cation disorder. We study this non-equilibrium problem via real space Monte Carlo on a disordered strong coupling model appropriate to the manganites. We reproduce the variation of the switching fields with the mean ionic radius r_A and cation disorder σ_A, and demonstrate how the experimental features arise from the proximity of several phases in the Landau free energy landscape. Our prediction for the field melted state is consistent with a growing body of experimental evidence.

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Anamitra Mukherjee, Kalpataru Pradhan, Pinaki Majumdar. 2009-03-20. Conductance Switching and Inhomogeneous Field Melting in the Charge Ordered Manganites. https://doi.org/10.1209/0295-5075%2F86%2F27003

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