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arXiv · 0807.3876

Correlation effects on the doped triangular lattice in view of the physics of sodium-rich Na$_x$CoO$_2$

Frank Lechermann
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Abstract

The peculiar correlation effects on the triangular lattice are studied by means of the rotationally invariant slave boson method in a cellular cluster approach. Hence nonlocal correlations are included in a short-range regime. Their impact for the single-band Hubbard model is studied at half filling, i.e., on the Mott transition, and with doping. Using the realistic band structure of Na$_x$CoO$_2$, we may also shed light on the cobaltate physics for $x$$\ge$1/3, with the in-plane transition from antiferromagnetic tendencies towards the onset of ferromagnetism for a finite Hubbard $U$.

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Frank Lechermann. 2009-01-30. Correlation effects on the doped triangular lattice in view of the physics of sodium-rich Na$_x$CoO$_2$. https://doi.org/10.1103/physrevlett.102.046403

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