paper

Electronic band structure of BaCo $_{2}$ As $_{2}$ : a fully-doped ferropnictide with reduced electronic correlations

arXiv:1210.5576 · doi:10.1103/PhysRevX.3.011006

Abstract

We report an angle-resolved photoemission spectroscopy investigation of the Fermi surface and electronic band structure of BaCo $_{2}$ As $_{2}$ . Although its quasi-nesting-free Fermi surface differs drastically from that of its Fe-pnictide cousins, we show that the BaCo $_{2}$ As $_{2}$ system can be used as an approximation to the bare unoccupied band structure of the related BaFe $_{2 - x}$ Co $_{x}$ As $_{2}$ and Ba $_{1 - x}$ K $_{x}$ Fe $_{2}$ As $_{2}$ compounds. However, our experimental results, in agreement with dynamical mean field theory calculations, indicate that electronic correlations are much less important in BaCo $_{2}$ As $_{2}$ than in the ferropnictides. Our findings suggest that this effect is due to the increased filling of the electronic 3 $d$ shell in the presence of significant Hund's exchange coupling.

6 pages, 4 figures

Electronic band structure of BaCo2​As2​: a fully-doped ferropnictide with reduced electronic correlations

Abstract

Electronic band structure of BaCo $_{2}$ As $_{2}$ : a fully-doped ferropnictide with reduced electronic correlations