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VOLUME 117 (2023) | ISSUE 11 |
PAGE 863
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Electron correlation effects in paramagnetic cobalt
A. S. Belozerov +, V. I. Anisimov *×
+Department of Physics, University of Hamburg, 20355 Hamburg, Germany *M. N. Mikheev Institute of Metal Physics, Russian Academy of Sciences, 620108 Yekaterinburg, Russia ×Ural Federal University, 620002 Yekaterinburg, Russia
Abstract
We study the influence of Coulomb correlations on spectral and
magnetic properties of fcc cobalt using a combination of density
functional theory and dynamical mean-field theory. The computed uniform
and local magnetic susceptibilities obey the Curie-Weiss law, which, as
we demonstrate, occurs due to the partial formation of local magnetic
moments. We find that the lifetime of these moments in cobalt is
significantly less than in bcc iron, suggesting a more itinerant
magnetism in cobalt. In contrast to the bcc iron, the obtained electronic
self-energies exhibit a quasiparticle shape with the quasiparticle mass
enhancement factor , corresponding to moderately
correlated metal. Finally, our calculations reveal that the static
magnetic susceptibility of cobalt is dominated by ferromagnetic
correlations, as evidenced by its momentum dependence.
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