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Anti-Localisation to Strong Localisation: The Interplay of Magnetic Scattering and Structural Disorder

Sanjeev Kumar·Pinaki Majumdar
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Abstract

We study the effect of magnetic scattering on transport in a system with strong structural disorder, using exact finite size calculation of the low frequency optical conductivity. At weak electron-spin coupling spin disorder leads to a decrease in resistivity by weakening the quantum interference precursors to Anderson localisation. However, at strong electron-spin coupling, the double exchange limit, magnetic scattering increases the effective disorder, sharply increasing the resistivity. We illustrate the several unusual transport regimes in this strong disorder problem, identify a re-entrant insulator-metal-insulator transition, and map out the phase diagram at a generic electron density.

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Sanjeev Kumar, Pinaki Majumdar. 2003-11-22. Anti-Localisation to Strong Localisation: The Interplay of Magnetic Scattering and Structural Disorder. https://doi.org/10.1209/epl%2Fi2003-10056-8

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