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arXiv · 0810.5093

Direct observation of the superconducting gap in phonon spectra

F. Weber·A. Kreyssig·L. Pintschovius·R. Heid·W. Reichardt·D. Reznik·O. Stockert·K. Hradil
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Abstract

We show that the superconducting energy gap $Δ$ can be directly observed in phonon spectra, as predicted by recent theories. In addition, since each phonon probes the gap on only a small part of the Fermi surface, the gap anisotropy can be studied in detail. Our neutron scattering investigation of the anisotropic conventional superconductor YNi$_2$B$_2$C demonstrates this new application of phonon spectroscopy.

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F. Weber, A. Kreyssig, L. Pintschovius, R. Heid, W. Reichardt, D. Reznik, O. Stockert, K. Hradil. 2008-10-28. Direct observation of the superconducting gap in phonon spectra. https://doi.org/10.1103/physrevlett.101.237002

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