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arXiv · 0705.3627

Coulomb correlations do not fill the e'_g hole pockets in Na_{0.3}CoO_2

A. Liebsch·H. Ishida
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Abstract

There exists presently considerable debate over the question whether local Coulomb interactions can explain the absence of the small e'_g Fermi surface hole pockets in photoemission studies of Na_{0.3}CoO_2. By comparing dynamical mean field results for different single particle Hamiltonians and exact diagonalization as well as quantum Monte Carlo treatments, we show that, for realistic values of the Coulomb energy U and Hund exchange J, the e'_g pockets can be slightly enhanced or reduced compared to band structure predictions, but they do not disappear.

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A. Liebsch, H. Ishida. 2007-05-24. Coulomb correlations do not fill the e'_g hole pockets in Na_{0.3}CoO_2. https://doi.org/10.1140/epjb/e2008-00108-y

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