On the scaling law of some characteristic fields in Y1−xPrxBa2Cu3O7−δ

We investigated the anisotropy dependence of the characteristic fields of the second peak magnetization, specifically, the onset field Bon and the peak field Bsp, in Y1−xPrxBa2Cu3O7−δ single crystals. The empirical dependence arising from data analysis suggests a logarithmic dependence of both these fields on the anisotropy factor γ   which disagrees with the universal scaling law γ2B=F(t)γ2B=F(t) proposed previously. We attribute the faster decrease of the two fields at high anisotropy to the dramatic changes in the magnetic state of the system which starts to display a noticeable paramagnetic contribution at high Pr-doping, hence high anisotropy. The incipient phase separation could also reduce the elastic properties of the flux line lattice which determines onset of the second peak magnetization.

Research highlights► Anisotropy γ dependence of the characteristic fields of Y1−xPrxBa2Cu3O7 is presented. ► The fields follow a logarithmic dependence on γ with the same scaling parameter. ► The faster decrease of the two fields at high γ could be due to the changes in the magnetic state of the system.