2002/09/18 by D. Reznik, L. Pintschovius, W. Reichardt +6
Physics and Astronomy · #cond-mat.supr-con #cond-mat.str-el
published as J. Low Temp. Phys., 131, 417 (2003) · 5 pages, 3 figures, To appear in Journal of Low Temperature Physics (Proceedings of MOS2002; Revised version (1) with many changes throughout the text
arxiv created 2002/09/18 · arxiv updated 2009/11/30
We report results of inelastic neutron scattering measurements of phonon dispersions on a detwinned sample of YBaCu3O7 and compare them with model calculations. Plane oxygen bond stretching phonon branches disperse steeply downwards from the zone center in both the a and the b direction indicating a strong electron-phonon coupling. Half way to the zone boundary, the phonon peaks become ill-defined but we see no need to invoke unit cell doubling or charge stripe formation: lattice dynamical shell model calculations predict such behavior as a result of branch anticrossings. There were no observable superconductivity-related temperature effects on selected plane oxygen bond stretching modes measured on a twinned sample.