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Low-energy excitations in NaV2O5

M. J. Konstantinovic·J. C. Irwin·M. Isobe·Y. Ueda
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Abstract

In the (ab) polarized Raman scattering spectra of NaV2O5 single crystals, measured with 647.1 nm laser line at T < Tc, we found two modes at 86, and 126 cm-1 not previously reported. These two modes, together with 66, and 106 cm-1 modes, make an array of four low-energy equidistant modes below the energy onset of the continuum at about 132 cm-1. All four modes are strongly suppressed by increasing Na deficiency, indicating their nonvibrational origin and the existence of a quantum phase transition at critical Na deficiency between 3 and 4%. These results question current understanding of NaV2O5 as quasi one-dimensional Heisenberg antiferromagnet.

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M. J. Konstantinovic, J. C. Irwin, M. Isobe, Y. Ueda. 2001-03-21. Low-energy excitations in NaV2O5. https://doi.org/10.1103/physrevb.65.012404

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