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Appearance of new lines and change in line shape in the IR spectrum of a NaV_2O_5 single crystal at the spin-Peierls transition

M. N. Popova·A. B. Sushkov·A. N. Vasil'ev·M. Isobe·Yu. Ueda
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Abstract

We report the first observation of new lines in the infrared spectrum of a crystal due to unit-cell doubling at the spin-Peierls transition (in NaV_2O_5). The change in the shape of the spectral lines at the spin-Peierls transition is recorded for the first time. A contour characteristic of a Fano resonance is observed above the transition temperature Tsp and the standard symmetric contour is observed below Tsp. We attribute this effect to the opening of a gap in the magnetic-excitation spectrum at the spin-Peierls transition.

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M. N. Popova, A. B. Sushkov, A. N. Vasil'ev, M. Isobe, Yu. Ueda. 1997-11-06. Appearance of new lines and change in line shape in the IR spectrum of a NaV_2O_5 single crystal at the spin-Peierls transition. https://doi.org/10.1134/1.567420

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