Artificial flux pinning in Nb and Nb/sub 3/Sn superconductors

Some results on artificial flux pinning centers (APCs) introduced into Nb filaments are reported. The APCs are copper in a nanometer scale which is comparable to the fluxon diameter. The preliminary results show a significant current density increase in APC samples compared with the cold worked Nb samples. The effect of APC on the upper critical field and superconducting transition temperature is also investigated. The effect of APC on the superconducting properties of Nb/sub 3/Sn which is formed by solid state diffusion process is also studied.<
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