Hund's metallicity and orbital-selective Mott localization of CrO$_{2}$ in the paramagnetic state

Mu-Yong Choi

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arXiv · 1611.05568

Hund's metallicity and orbital-selective Mott localization of CrO$_{2}$ in the paramagnetic state

Mu-Yong Choi

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Abstract

We present electronic structure calculations of a CrO$_{2}$ compound in the paramagnetic state within the computational scheme of density-functional theory combined with dynamical mean-field theory. We find that CrO$_{2}$ in the paramagnetic state is a strongly-correlated Hund's metal with mixed-valent Cr ions. At high temperatures, CrO$_{2}$ shows an orbital-selective Mott phase, in which the Cr $d_{xy}$ orbital is Mott-localized while the other Cr $t_{2g}$ $d$ orbitals remain itinerant. When the temperature is lowered, the orbital-selective Mott state is found to evolve into a Kondo-like heavy-fermion state with a small pseudo gap at the Fermi level if the system remains in the paramagnetic state.

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Mu-Yong Choi. 2016-11-17. Hund's metallicity and orbital-selective Mott localization of CrO$_{2}$ in the paramagnetic state. https://arxiv.org/abs/1611.05568

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