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arXiv · 1007.0182

Superconductivity-Induced Distortions of Phonon Lineshapes in Niobium

F. Weber·L. Pintschovius
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Abstract

Superconductivity-induced changes of phonon lineshapes in niobium have been re-investigated by high-resolution inelastic neutron scattering. We show that the changes go beyond a simple change in lifetime and frequency when the phonon frequency is close to the superconducting energy gap $2\Delta$. The observed lineshapes in elemental niobium are qualitatively similar to those found previously in borocarbide superconductors and agree very well with those predicted by the theory of Allen et al. [PRB 56, 5552 (1997)]. Our results indicate that the peculiar phonon lineshapes in the superconducting state predicted by the theory of Allen et al. are a general phenomenon and not restricted to a particular class of compounds.

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F. Weber, L. Pintschovius. 2010-07-01. Superconductivity-Induced Distortions of Phonon Lineshapes in Niobium. https://doi.org/10.1103/physrevb.82.024509

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