Details

Autor(en) / Beteiligte

• Sarun, Pallian Murikoli
• Biju, Alikunju
• Guruswamy, Perumal
• Syamaprasad, Upendran

Titel

Enhanced Flux Pinning of an Nd-Added (Bi,Pb)-2212 Superconductor

Ist Teil von

• Journal of the American Ceramic Society, 2007-10, Vol.90 (10), p.3138-3141

Ort / Verlag

Malden, USA: Blackwell Publishing Inc

Erscheinungsjahr

2007

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• The flux pinning properties of a (Bi,Pb)‐2212 superconductor by the addition of a rare‐earth element Nd with varying concentrations were studied. The Nd content of the samples was varied from x=0.0 to 0.5 on a general stoichiometry of Bi1.7Pb0.4Sr2.0Ca1.1Cu2.1NdxOy. The samples were characterized by powder X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray analysis, and transport critical current measurements at 64 K. Both self‐field JC and JC in the presence of an applied magnetic field (JC–B) of Nd‐added samples were found to be much better than those of the pure sample. Also, the peak values of the bulk pinning force density (FPmax) of Nd‐added samples shift toward higher magnetic fields, indicative of the enhanced flux pinning strength of the samples. The results are explained based on the replacement of cations such as Sr2+, Ca2+, and Bi3+ by Nd3+ ions and the associated distortion of the lattice and change in hole concentration in the system. The replacement produced point‐like defects due to the difference in the ionic radii of Sr2+ (1.12 Å), Ca2+ (0.99 Å), Bi3+ (0.96 Å), and Nd3+ (1.04 Å). The nanoscale secondary phase precipitates produced due to Nd addition may also act as flux pinners.