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Published on: April 12, 2018
Theory of carrier concentration-dependent electronic behavior in layered cobaltates
1Department of Physics, University of Arizona, Tucson, Arizona 85721, USA.
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) hole occupancy within the latter.
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