Naslov
Flux-pinning and inhomogeneity in MgB_2/Fe wires

Autori
Husnjak, Ozren ; Babić, Emil ; Kušević, Ivica ; Wang, Xiao Lin ; Soltanian, Saeid ; Dou, Shi Xue

Izvornik
Solid State Communications (0038-1098) 143 (2007), 8-9; 412-415

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
superconductors; flux pinning and creep

Sažetak
Transport critical current densities J_c and irreversibility fields B_irr of undoped and nanoparticle doped (10 wt% SiC) Fe-sheathed MgB_2 wires were measured from 2 to 40K in magnetic field B<16T. For the best segments of wires (<1 cm)both the magnitude and field variations of J_c and the pinning force density F_p=J_cB depend only on the magnitude of B_irr, hence the strength of flux-pinning. B_irr of doped wire for T<30K is ~1.4 times larger than that of undoped and reaches that of NbTi (10T at 4.2K) already at 20K. Accordingly, its high-field J_c s and F_p s are large, typically three times larger than the best literature results, and are limited by the porosity and inhomogeneity of the superconducting cores in present-day MgB_2 wires.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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