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arXiv · 1208.4500

Cuprates, Manganites, and Cobaltites: Multielectron Approach to the Band Structure

M. M. Korshunov·S. G. Ovchinnikov·E. I. Shneyder·V. A. Gavrichkov·Yu. S. Orlov·I. A. Nekrasov·Z. V. Pchelkina
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Abstract

High-$T_c$ superconductors with CuO$_2$ layers, manganites La$_{1-x}$Sr$_x$MnO$_3$, and cobaltites LaCoO$_3$ present several mysteries in their physical properties. Most of them are believed to come from the strongly-correlated nature of these materials. From the theoretical viewpoint, there are many hidden rocks in making the consistent description of the band structure and low-energy physics starting from the Fermi-liquid approach. Here we discuss the alternative method -- multielectron approach to the electronic structure calculations for the Mott insulators -- called LDA+GTB (local density approximation + generalized tight-binding) method. Its origin is a straightforward generalization of the Hubbard perturbation theory in the atomic limit and the multiband $p-d$ Hamiltonian with the parameters calculated within LDA. We briefly discuss the method and focus on its applications to cuprates, manganites, and cobaltites.

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M. M. Korshunov, S. G. Ovchinnikov, E. I. Shneyder, V. A. Gavrichkov, Yu. S. Orlov, I. A. Nekrasov, Z. V. Pchelkina. 2012-08-22. Cuprates, Manganites, and Cobaltites: Multielectron Approach to the Band Structure. https://doi.org/10.1142/s0217984912300165

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