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Ferromagnetic transition in a double-exchange system containing impurities in the Dynamical Mean Field Approximation

Mark Auslender·Eugene Kogan
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Abstract

We formulate the Dynamical Mean Field Approximation equations for the double-exchange system with quenched disorder for arbitrary relation between Hund exchange coupling and electron band width. Close to the ferromagnetic-paramagnetic transition point the DMFA equations can be reduced to the ordinary mean field equation of Curie-Weiss type. We solve the equation to find the transition temperature and present the magnetic phase diagram of the system.

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Mark Auslender, Eugene Kogan. 2002-03-27. Ferromagnetic transition in a double-exchange system containing impurities in the Dynamical Mean Field Approximation. https://doi.org/10.1209/epl%2Fi2002-00238-x

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