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Half-Metallic Ferromagnetism and the spin polarization in CrO$_2$

L. Chioncel·H. Allmaier·E. Arrigoni·A. Yamasaki·M. Daghofer·M. I. Katsnelson·A. I. Lichtenstein
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Abstract

We present electronic structure calculations in combination with local and non-local many-body correlation effects for the half-metallic ferromagnet CrO$_2$. Finite-temperature Dynamical Mean Field Theory results show the existence of non-quasiparticle states, which were recently observed as almost currentless minority spin states near the Fermi energy in resonant scattering experients. At zero temperatures, Variational Cluster Approach calculations support the half-metallic nature of CrO$_2$ as seen in superconducting point contact spectroscopy. The combination of these two techniques allowed us to qualitatively describe the spin-polarization in CrO$_2$.

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L. Chioncel, H. Allmaier, E. Arrigoni, A. Yamasaki, M. Daghofer, M. I. Katsnelson, A. I. Lichtenstein. 2007-03-02. Half-Metallic Ferromagnetism and the spin polarization in CrO$_2$. https://doi.org/10.1103/physrevb.75.140406

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