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arXiv · 0704.1048

Anisotropic quasiparticle renormalization in Na0.73CoO2: role of inter-orbital interactions and magnetic correlations

J. Geck·S. V. Borisenko·H. Berger·H. Eschrig·J. Fink·M. Knupfer·K. Koepernik·A. Koitzsch·A. A. Kordyuk·V. B. Zabolotnyy·B. Buechner
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Abstract

We report an angular resolved photoemission study of Na0.73CoO2 where it is found that the renormalization of the quasiparticle (QP) dispersion changes dramatically upon a rotation from GM to GK. The comparison of the experimental data to the calculated band structure reveals that the QP-renormalization is most pronounced along the GK-direction, while it is significantly weaker along the GM-direction. We discuss the observed anisotropy in terms of multiorbital effects and point out the relevance of magnetic correlations for the band structure of Na0.73CoO2.

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J. Geck, S. V. Borisenko, H. Berger, H. Eschrig, J. Fink, M. Knupfer, K. Koepernik, A. Koitzsch, A. A. Kordyuk, V. B. Zabolotnyy, B. Buechner. 2007-04-10. Anisotropic quasiparticle renormalization in Na0.73CoO2: role of inter-orbital interactions and magnetic correlations. https://doi.org/10.1103/physrevlett.99.046403

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