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Orbital Correlations in the Ferromagnetic Half-Metal $CrO_{2}

M. S. Laad·L. Craco·E. Müller-Hartmann
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Abstract

We deduce a model relevant for the description of the ferromagnetic half-metal Chromium dioxide ($CrO_{2}$), widely used in magnetic recording technology. The model describes the effect of dynamical, local orbital correlations arising from local quantum chemistry of the material. A finite temperature solution of the model in $d=\infty$ provides a natural explanation of the optical response, photoemission, resistivity and the large Woods-Saxon ratio observed in experiments. Our study confirms the important role of many body dynamical correlation effects for a proper understanding of the metallic phase of $CrO_{2}$.

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M. S. Laad, L. Craco, E. Müller-Hartmann. 2001-01-22. Orbital Correlations in the Ferromagnetic Half-Metal $CrO_{2}. https://doi.org/10.1103/physrevb.64.214421

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