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Low temperature ellipsometry of NaV2O5

C. Presura·D. van der Marel·A. Damascelli·R. K. Kremer
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Abstract

The dielectric function of alpha'NaV2O5 was measured with electric field along the a and b axes in the photon energy range 0.8-4.5 eV for temperatures down to 4K. We observe a pronounced decrease of the intensity of the 1 eV peak upon increasing temperature with an activation energy of about 25meV, indicating that a finite fraction of the rungs becomes occupied with two electrons while others are emptied as temperature increases. No appreciable shifts of peaks were found s in the valence state of individual V atoms at the phase transition is very small. A remarkable inflection of this temperature dependence at the phase transition at 34 K indicates that charge ordering is associated with the low temperature phase.

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C. Presura, D. van der Marel, A. Damascelli, R. K. Kremer. 2000-05-22. Low temperature ellipsometry of NaV2O5. https://doi.org/10.1103/physrevb.61.15762

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