X-Ray, Neutron and Magnetization Studies of YBa₂Cu₃O_7-x Irradiated by Fast Neutrons

The influence of fast neutron irradiation on the structure and the magnetic properties of YBa2Cu3O7−x has been studied. Samples irradiated with fluences between 4.0 × 1016 and 8.7 × 1017 n/cm2 were investigated. The magnetization measurements showed a significant increase of the magnetization currents for fluence up to 2.3 × 1017 n/cm2 when saturation was reached.

Investigations of the average crystal structure by X-ray and neutron powder diffraction show as the essential change a linear increase of the lattice constants a, b and c for small values of fluence and a decrease at higher fluences. A nearly isotropic variation of all three lattice parameters is observed for fluences below 1.2 × 1017 n/cm2 Any other changes of the microscopic crystallographic parameters are smaller than the statistical errors or the systematic differences between the X-ray and the neutron results.