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Charge excitations in LiV$_{2}$O$_{5}$ and NaV$_{2}$O$_{5}$: similarities and differences

A. Huebsch·C. Waidacher·K. W. Becker
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Abstract

We calculate the optical conductivity of LiV$_{2}$O$_{5}$ and NaV$_{2}$O$_{5}$ using exact numerical diagonalization of a quarter-filled extended Hubbard model on a system of coupled ladders. In particular, electronic correlations are treated exactly, and a quantitative agreement between calculated and experimentally observed optical conductivity of these two vanadium oxides is presented. Furthermore, it is found that LiV$_{2}$O$_{5}$ differs from NaV$_{2}$O$_{5}$ not only in the charge ordering pattern but also in the nature of the inter-ladder coupling: In contrast to LiV$_{2}$O$_{5}$, in NaV$_{2}$O$_{5}$ neighboring ladders are coupled by a strong Coulomb repulsion, and not by inter-ladder hopping.

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A. Huebsch, C. Waidacher, K. W. Becker. 2001-08-03. Charge excitations in LiV$_{2}$O$_{5}$ and NaV$_{2}$O$_{5}$: similarities and differences. https://doi.org/10.1103/physrevb.64.241103

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