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arXiv · 1012.3118

Theory of carrier concentration-dependent electronic behavior in layered cobaltates

H. Li·R. T. Clay·S. Mazumdar
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Abstract

A natural explanation for the carrier concentration-dependent electronic behavior in the layered cobaltates emerges within correlated-electron Hamiltonians with finite on-site and significant nearest neighbor hole-hole Coulomb repulsions. The nearest neighbor repulsion decreases hole double-occupancy below hole density 1/3, but increases the same at higher hole densities. Our conclusion is valid for both single-band and three-band extended Hubbard Hamiltonians, and sheds light on concentration-dependent $e_g^\prime$ hole occupancy within the latter.

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H. Li, R. T. Clay, S. Mazumdar. 2011-03-28. Theory of carrier concentration-dependent electronic behavior in layered cobaltates. https://doi.org/10.1103/physrevlett.106.216401

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