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Metal-insulator transition in the double perovskites

A. A. Aligia·P. Petrone·J. O. Sofo·B. Alascio
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Abstract

We construct an effective Hamiltonian for the motion of electrons among the transition metal ions of ordered double perovskites like Sr2FeMoO6. in which strong intra-atomic Coulomb repulsion U is present in only one of the inequivalent transition metal sites. Using a slave-boson formalism, we construct a phase diagram which describes a charge transfer transition between insulating and metallic behavior as the parameters of the model are changed. The parameters for Sr2FeMoO6 are estimated from first-principles calculations and a transition to the insulating state with negative pressure is obtained.

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A. A. Aligia, P. Petrone, J. O. Sofo, B. Alascio. 2001-05-29. Metal-insulator transition in the double perovskites. https://doi.org/10.1103/physrevb.64.092414

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