%0 Journal Article %1 Pintschovius2004 %A Pintschovius, L. %A Reznik, D. %A Reichardt, W. %A Endoh, Y. %A Hiraka, H. %A Tranquada, J. M. %A Uchiyama, H. %A Masui, T. %A Tajima, S. %D 2004 %I American Physical Society %J Phys. Rev. B %K imported %N 21 %P 214506 %R 10.1103/PhysRevB.69.214506 %T Oxygen phonon branches in $YBa2Cu3O7$ %V 69 %X We report results of inelastic neutron scattering measurements of phonon dispersions in optimally doped YBa2Cu3O6.95 and compare them with model calculations. The focus is on the in-plane oxygen bond-stretching phonon branches. The study of these modes is complicated by anticrossings with c-axis-polarized branches; such effects are interpreted through lattice-dynamical shell-model calculations. The in-plane anisotropy of the bond-stretching phonons was firmly ascertained from measurements on a detwinned sample. Studying not only the in-plane modes involving in-phase motion for the two Cu-O layers within a unit cell but also those with opposite-phase motion was of great help for establishing a clear experimental picture. The measurements confirm that the in-plane oxygen bond-stretching phonon branches disperse steeply downwards from the zone center in both the a and the b directions indicating a strong electron-phonon coupling. For the b-axis-polarized bond-stretching phonons, there is an additional feature of considerable interest: a sharp local frequency minimum was found to develop on cooling from room temperature to T=10K at wave vector q≈0.27 r.l.u.

@article{Pintschovius2004, abstract = {We report results of inelastic neutron scattering measurements of phonon dispersions in optimally doped YBa2Cu3O6.95 and compare them with model calculations. The focus is on the in-plane oxygen bond-stretching phonon branches. The study of these modes is complicated by anticrossings with c-axis-polarized branches; such effects are interpreted through lattice-dynamical shell-model calculations. The in-plane anisotropy of the bond-stretching phonons was firmly ascertained from measurements on a detwinned sample. Studying not only the in-plane modes involving in-phase motion for the two Cu-O layers within a unit cell but also those with opposite-phase motion was of great help for establishing a clear experimental picture. The measurements confirm that the in-plane oxygen bond-stretching phonon branches disperse steeply downwards from the zone center in both the a and the b directions indicating a strong electron-phonon coupling. For the b-axis-polarized bond-stretching phonons, there is an additional feature of considerable interest: a sharp local frequency minimum was found to develop on cooling from room temperature to T=10K at wave vector q≈0.27 r.l.u.}, added-at = {2010-11-06T00:14:39.000+0100}, author = {Pintschovius, L. and Reznik, D. and Reichardt, W. and Endoh, Y. and Hiraka, H. and Tranquada, J. M. and Uchiyama, H. and Masui, T. and Tajima, S.}, biburl = {https://www.bibsonomy.org/bibtex/294a350c9fefb1c21dce037d3504f2949/nplumb}, doi = {10.1103/PhysRevB.69.214506}, file = {:C\:\\Users\\Nick\\Documents\\Papers\\Pintschovius, Reznik & Reichardt - Oxygen phonon branches in YBa2Cu3O7.pdf:PDF}, interhash = {197cb64f8ac56f57f405e9e6e5c3b2e2}, intrahash = {94a350c9fefb1c21dce037d3504f2949}, journal = {Phys. Rev. B}, keywords = {imported}, month = Jun, number = 21, numpages = {11}, owner = {Nick}, pages = 214506, publisher = {American Physical Society}, timestamp = {2010-11-06T00:14:43.000+0100}, title = {Oxygen phonon branches in $YBa2Cu3O7$}, volume = 69, year = 2004 }