Inelastic X-ray Scattering Study of Phonons in Superconducting CaC6

M. H. Upton; A. C. Walters; C. A. Howard; K. C. Rahnejat; M. Ellerby; J. P. Hill; D. F. McMorrow; A. Alatas; Bogdan M. Leu; Wei Ku

arXiv · 0709.1179

Inelastic X-ray Scattering Study of Phonons in Superconducting CaC6

M. H. Upton·A. C. Walters·C. A. Howard·K. C. Rahnejat·M. Ellerby·J. P. Hill·D. F. McMorrow·A. Alatas·Bogdan M. Leu·Wei Ku

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Abstract

We investigate the dispersion and temperature dependence of a number of phonons in the recently discovered superconductor CaC6 utilizing inelastic x-ray scattering. Four [00L] and two ab-plane phonon modes are observed, and measured at temperatures both above and below T_c. In general, our measurements of phonon dispersions are in good agreement with existing theoretical calculations of the phonon dispersion. This is significant in light of several discrepancies between experimental measurements of phonon-derived quantities and theoretical calculations. The present work suggests that the origin of these discrepancies lies in the understanding of the electron-phonon coupling in this material, rather than in the phonons themselves.

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M. H. Upton, A. C. Walters, C. A. Howard, K. C. Rahnejat, M. Ellerby, J. P. Hill, D. F. McMorrow, A. Alatas, Bogdan M. Leu, Wei Ku. 2007-10-30. Inelastic X-ray Scattering Study of Phonons in Superconducting CaC6. https://arxiv.org/abs/0709.1179

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