Lattice Dynamics of the High Tc Superconductor ErBa2Cu3O7

Abstract

The lattice dynamics of the high Tc superconductor ErBa2Cu307 have been investigated in detail with a modified three-body force shell model. The model accounts for the effect of many-body interactions in the lattice potential. The aim of the present work is to treat the various interactions between the ions in generalised way without making them numerically equal. The values of the phonon frequencies calculated at the zone centre by this new approach are in good agreement with the available Raman and infrared data.