Enhanced Pinning Properties of Laser-Irradiated Bulk MgB2 Superconductors
In order to investigate the effect of laser irradiation on the superconducting properties of MgB2, a pellet-shaped sample was produced and cut into two pieces. The dot-shaped molten patterns, with the distance of 100 µm between them, were formed on the surface of one of the pieces by using an Nd:YVO4 laser. The grains of the irradiated sample were significantly grown due to the laser-induced sintering. The modified surface appeared to have dense and compacted grains as a result of increasing interconnectivity among the superconducting grains. The critical current densities at 5 K in a field of 3 T were found to be 5.38 × 104 and 8.96 × 104 A cm?2 for the reference and the irradiated samples, respectively. The increment of critical current density for the irradiated sample is presumably connected with the changing of pinning mechanism after the laser irradiation. For the irradiated sample which showed a higher value of critical current density at 5 K under high fields, ?? pinning was obtained as a dominant pinning mechanism, while the normal point pinning was dominant for the reference one. These results point out that the superconducting properties of bulk MgB2 can be changed and improved via laser irradiation in a short time. © 2016, Springer Science+Business Media New York.
SourceJournal of Superconductivity and Novel Magnetism
Showing items related by title, author, creator and subject.
MgB2 bulk sample with porous structure was produced by using the in-situ solid-state reaction method under argon (Ar) atmosphere of 10 bar. Elemental Er in powder form was doped into MgB2 with different compositions ...
Clarification of magnetic levitation force and stability property of multi-seeded YBCO in point of supercurrent coupling effect In our study as different from the literature, which are mostly related to superconductor fabrication, application and optimization, especially physical origins of bulk supercurrent generation, magnetic levitation and ...
Effect of laser irradiation on activation energy, irreversibility field and upper critical magnetic field of bulk MgB2 superconductor In this study, the role of laser irradiation on the upper critical field (Hc2), the irreversibility field (Hirr) and the activation energy (U0) of bulk MgB2 superconductor was first time investigated with the aid of ...