CRYSTAL FIELDS IN RBA(2)CU(4)O(8) SUPERCONDUCTORS STUDIED BY INELASTIC NEUTRON-SCATTERING

Neutron spectroscopy has been used to study the crystal field excitation spectra in high quality samples of RBa(2)Cu(4)O(8) high temperature superconductors, with R = Dy, Ho and Er. The samples were prepared under high oxygen pressure. Analysis of the spectra included treatment of the spin-orbit and Coulomb interactions, sad yielded crystal field parameters which showed a high degree of consistency from one rare earth to another.