Flux jump behaviors and mechanism of FeTi doped MgB2 at 5 K

Abstract This study examined the flux jump behaviors of Fe-doped MgB 2 according to content of FeTi particles at 5 K, at which flux jump has been shown to be more frequent. The samples were synthesized in a stainless steel tube with Mg, B and FeTi particles. The motives of flux jump in MgB 2 superconductors are over-moving fluxes around the defects and the low heat capacity of MgB 2 . MgB 2 was doped with FeTi particles to overcome these vulnerable points of MgB 2 . The flux jump of MgB 2 decreased with increasing content of doped FeTi particles. On the other hand, excessive doping of FeTi resulted in a decrease of diamagnetic properties and the flux pinning effects together. It is concluded that FeTi particles in MgB 2 do not block the flux jump itself, but the propagation of flux jump of MgB 2 .