New Scaling Laws for Pinning Force Density in Superconductors

Since the report by Fietz and Webb (Phys. Rev.1968, 178, 657–667), who considered pinning force density, Fp→=Jc→×B→ (where Jc is critical current density B applied magnetic flux density), in isotropic superconductors as a unique function of reduced field, BBc2 Bc2 upper field), Fp→ has been scaled based on ratio, for which there widely used Kramer–Dew–Hughes scaling law Fp→B=Fp,maxBBc2p1−BBc2q, where Fp,max, Bc2, p, q are free-fitting parameters. To describe Fp→B high-temperature superconductors, modified (a) an assumption angular dependence all parameters (b) replacement irreversibility Birr. Here, we note that also thus, Fp→Jc should exist. In attempt to reveal this law, full Fp→B,Jc reported three distinctive characteristic ranges BBc2,JcJcsf Jcsf self-field density) can be splatted. Several new laws were proposed MgB2, NdFeAs(O,F), REBCO, (La,Y)H10, YH6. The in-field performance at low moderate fields, primary niche these superconducting wires tapes cables, fault limiters, transformers.