arXiv subjects

Ph. Werner

Publications and source records attributed to Ph. Werner.

3 recordsLinked to original sources

arXiv2018

Linear behavior of the optical conductivity and incoherent charge transport in BaCoS2

Optical conductivity measurements on a BaCoS2 single crystal show an unusual linear behavior over a broad spectral range. In the paramagnetic phase above 300 K, the spectrum shows no gap, which contradicts the previously proposed scenario of a charge-transfer Mott insulator. Ab initio dynamical mean field theory calculations including a retarded Hubbard interaction explain the data in terms of an incipient opening of a Co(3d)-S(3p) charge-transfer gap concomitant to incoherent charge transport driven by electronic correlations. These results point to a non-Fermi liquid scenario with Hund's metal properties in the paramagnetic state, which arises from an incipient Mott phase destabilized by low-energy charge fluctuations across the vanishing 3d-3p charge-transfer gap.

cond-mat.str-el↗

arXiv2013

Consistent description of the electronic structure of SrVO$_{3}$ within GW+DMFT

We present a detailed calculation of the electronic structure of SrVO$_{3}$ based on the GW+DMFT method. We show that a proper inclusion of the frequency-dependent Hubbard U and the nonlocal self-energy via the GW approximation, as well as a careful treatment of the Fermi level, are crucial for obtaining an accurate and coherent picture of the quasi-particle band structure and satellite features of SrVO$_{3}$. The GW+DMFT results for SrVO$_{3}$ are not attainable within the GW approximation or the LDA+DMFT scheme.

cond-mat.str-el↗

arXiv2012

Low-energy models for correlated materials: bandwidth renormalization from Coulombic screening

We provide a prescription for constructing Hamiltonians representing the low energy physics of correlated electron materials with dynamically screened Coulomb interactions. The key feature is a renormalization of the hopping and hybridization parameters by the processes that lead to the dynamical screening. The renormalization is shown to be non-negligible for various classes of correlated electron materials. The bandwidth reduction effect is necessary for connecting models to materials behavior and for making quantitative predictions for low-energy properties of solids.

cond-mat.str-el↗