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Nature of insulating state in NaV$_{2}$O$_{5}$ above charge-ordering transition: a cluster DMFT study

V. V. Mazurenko·A. I. Lichtenstein·M. I. Katsnelson·I. Dasgupta·T. Saha-Dasgupta·V. I. Anisimov
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Abstract

The nature of insulating state driven by electronic correlations in the quarter-filled ladder compound $α'$NaV$_{2}$O$_{5}$ is investigated within a cluster dynamical mean-field approach. An extended Hubbard model with first-principle tight-binding parameters have been used. It is shown that the insulating state in the charge-disordered phase of this compound is formed due to the transfer of spectral density and dynamical charge fluctuations where for the latter, the role of inter-site Coulomb interaction is found to be of crucial importance.

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V. V. Mazurenko, A. I. Lichtenstein, M. I. Katsnelson, I. Dasgupta, T. Saha-Dasgupta, V. I. Anisimov. 2001-07-10. Nature of insulating state in NaV$_{2}$O$_{5}$ above charge-ordering transition: a cluster DMFT study. https://doi.org/10.1103/physrevb.66.081104

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