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Effect of Dynamical Coulomb Correlations on the Fermi Surface of Na_0.3CoO_2

H. Ishida·M. D. Johannes·A. Liebsch
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Abstract

The t2g quasi-particle spectra of Na_0.3CoO_2 are calculated within the dynamical mean field theory. It is shown that as a result of dynamical Coulomb correlations charge is transfered from the nearly filled e_g' subbands to the a_1g band, thereby reducing orbital polarization among Co t2g states. Dynamical correlations therefore stabilize the small e_g' Fermi surface pockets, in contrast to angle-resolved photoemission data, which do not reveal these pockets.

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H. Ishida, M. D. Johannes, A. Liebsch. 2005-04-21. Effect of Dynamical Coulomb Correlations on the Fermi Surface of Na_0.3CoO_2. https://doi.org/10.1103/physrevlett.94.196401

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