A novel technique for identification of minor superconducting phases

A novel technique that involves isolating and characterizing particles of p ulverized samples has been developed to identify minor superconducting phas es. Particles as small as 10 mum can be analyzed both magnetically and stru cturally. Data on several multi-phase Ba-Ca-Cu-O-(C) samples demonstrate th at the technique can even distinguish coexisting superconducting phases bas ed on the difference of the transition temperature T-c. Using the technique , (Ba0.95C0.05)(2)CuO4-delta was identified as superconducting with a T-c u p to 60 K and lattice parameters a approximate to b approximate to 3.85 Ang strom and c approximate to 15.7 Angstrom. (C) 2001 Elsevier Science B.V. Al l rights reserved.