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arXiv · 0801.4184

Phase Diagram of Na$_x$CoO$_2$ Studied by Gutzwiller Density Functional Theory

Guangtao Wang·Xi Dai·Zhong Fang
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Abstract

The ground states of Na$_x$CoO$_2$ ($0.0 0.6$ due to $a_{1g}$ van-Hove singularity near band top; (2) correlated non-magnetic metal without $e_g^{\prime}$ pockets for $0.3<x<0.6$; (3) $e_g^{\prime}$ pockets appear for $x<0.3$, and additional magnetic instability involves. Experimental quasi-particle properties is well explained, and the $a_{1g}$-$e_g^{\prime}$ anti-crossing is attributed to spin-orbital coupling.

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Guangtao Wang, Xi Dai, Zhong Fang. 2008-01-28. Phase Diagram of Na$_x$CoO$_2$ Studied by Gutzwiller Density Functional Theory. https://doi.org/10.1103/physrevlett.101.066403

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