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Electron-phonon and spin-phonon coupling in NaV$_{2}$O$_{5}$: charge fluctuations effect

E. Ya. Sherman·M. Fischer·P. Lemmens·P. H. M. van Loosdrecht·G. Güntherodt
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Abstract

We show that the asymmetric crystal environment of the V site in the ladder compound NaV$_{2}$O$_{5}$ leads to a strong coupling of vanadium 3d electrons to phonons. This coupling causes fluctuations of the charge on the V ions, and favors a transition to a charge-ordered state at low temperatures. In the low temperature phase the charge fluctuations modulate the spin-spin superexchange interaction, resulting in a strong spin-phonon coupling.

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E. Ya. Sherman, M. Fischer, P. Lemmens, P. H. M. van Loosdrecht, G. Güntherodt. 1999-10-25. Electron-phonon and spin-phonon coupling in NaV$_{2}$O$_{5}$: charge fluctuations effect. https://doi.org/10.1209/epl%2Fi1999-00533-6

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