Tuning the peak effect in the Y1-xNdxBa2Cu3O7-delta compound

Polycrystalline Y_1−xNd_xBa₂Cu₃O_7−δ (x=0.02, 0.11, and 0.25) superconductors are synthesized. Nd atoms are uniformly distributed over grains. The magnetization loops of the samples have a pronounced second peak in a wide temperature range. The magnetization data are analyzed using the extended critical state model. It is found that the order-disorder transition of the vortex lattice is affected by doping with neodymium and temperature; the second-peak field and width decrease monotonically with increasing x value. The undoped polycrystalline YBa₂Cu₃O_7−δ compound is assumed to exhibit the peak effect in higher magnetic fields.