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The semiconductor-to-ferromagnetic-metal transition in FeSb2

A. V. Lukoyanov·V. V. Mazurenko·V. I. Anisimov·M. Sigrist·T. M. Rice
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Abstract

We propose FeSb2 to be a nearly ferromagnetic small gap semiconductor, hence a direct analog of FeSi. We find that despite different compositions and crystal structures, in the local density approximation with on-site Coulomb repulsion correction (LDA+U) method magnetic and semiconducting solutions for U=2.6 eV are energetically degenerate similar to the case of FeSi. For both FeSb2 and FeSi (FeSi1-xGex alloys) the underlying transition mechanism allows one to switch from a small gap semiconductor to a ferromagnetic metal with magnetic moment 1 muB per Fe ion with external magnetic field.

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A. V. Lukoyanov, V. V. Mazurenko, V. I. Anisimov, M. Sigrist, T. M. Rice. 2006-10-22. The semiconductor-to-ferromagnetic-metal transition in FeSb2. https://doi.org/10.1140/epjb%2Fe2006-00361-0

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