Neutron scattering studies of Bi2Sr2Ca0.5Ho0.5Cu2O8+x

Neutron scattering has been employed to study the crystalline electric field (CEF) interaction at the Ho3+ site in Bi2Sr2Ca0.5Ho0.5Cu2O8+x. The observed energy spectra exhibit a large number of broad but well-resolved CEF transitions between 1.2 and 73 meV, so that we have been able to unambiguously determine all nine CEF parameters required for the average orthorhombic symmetry. The unusually large line widths of the CEF transitions are shown to be related to the modulated structure. The CEF potential is essentially governed by the charge distribution of the CuO2 planes which turns out to be very similar as in HoBa2Cu3O7-x.