In order to study the possibility of enhancing the electron-phonon coupling in cuprates by soft transverse acoustic TA modes, using high-resolution (dE=1.3 meV) inelastic x-ray scattering, we measured the inplane TA mode at low qd0.1 along the a* axis on optimally doped untwinned YBa2Cu3O(7-delta) single crystals. We find that the dispersion is linear with no softening down to q=0.02 and unchanged upon cooling from 300 to 98 K. The sound velocity is found to be 2700±70 m/s, in agreement with ultrasound data. Thus, no bending instability exists in the CuO2 layers and we conclude that larger and Tc may be possible in cuprates by inducing this instability.
Long-wavelength dispersion of transverse acoustic phonons in untwinned YBa2Cu3O(7-delta) single crystals
Licci F;
2007
Abstract
In order to study the possibility of enhancing the electron-phonon coupling in cuprates by soft transverse acoustic TA modes, using high-resolution (dE=1.3 meV) inelastic x-ray scattering, we measured the inplane TA mode at low qd0.1 along the a* axis on optimally doped untwinned YBa2Cu3O(7-delta) single crystals. We find that the dispersion is linear with no softening down to q=0.02 and unchanged upon cooling from 300 to 98 K. The sound velocity is found to be 2700±70 m/s, in agreement with ultrasound data. Thus, no bending instability exists in the CuO2 layers and we conclude that larger and Tc may be possible in cuprates by inducing this instability.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
