Enhancement of critical current density and flux pinning in acetone and La₂O₃ codoped MgB2 tapes

MgB₂ tape samples with simultaneous additions of acetone and La2O3 were prepared by an in-situ processed powder-in-tube method. Compared to the pure and single doped tapes, both transport and fluxing pinning are greatly improved by acetone and La₂O₃ codoping. Acetone supplies carbon into the MgB₂ crystal lattice and increases the upper critical field, while the La₂Oi reacts with B to form LaB6 nanoparticles as effective flux pining centers. The improvement of the superconducting properties in codoped tapes can be attributed to the combined effects of improvement in H₂ and flux pinning.