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CPA density of states and conductivity in a double-exchange system containing impurities

Mark Auslender·Eugene Kogan
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Abstract

We study density of states and conductivity of the doped double-exchange system, treating interaction of charge carriers both with the localized spins and with the impurities in the coherent potential approximation. It is shown that under appropriate conditions there is a gap between the conduction band and the impurity band in paramagnetic phase, while the density of states is gapless in ferromagnetic phase. This can explain metal-insulator transition frequently observed in manganites and magnetic semiconductors. Activated conductivity in the insulator phase is numerically calculated.

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Mark Auslender, Eugene Kogan. 2001-01-05. CPA density of states and conductivity in a double-exchange system containing impurities. https://doi.org/10.1007/s100510170298

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