Thermal Release of Hidden Magnetic Moments in High T-c Bi:2223/Ag Superconducting Tape During Warming to T-c

Celebi S., LeBlanc M. A. R.

JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM, vol.25, no.4, pp.791-797, 2012 (SCI-Expanded) identifier identifier


We report on measurements of the evolution of the magnetization aOE (c) M >, upon warming from T (0) (77 K) to T (c) , for Bi:2223/Ag tape prepared by the continuous filling and forming (CTFF) with the locus of aOE (c) M > initially situated along bridges between the envelopes of the major hysteresis curves. Concentric, oppositely directed magnetic moments coexist in the specimens when aOE (c) M > lies along the bridges. We focused on the cases where aOE (c) M >=0, hence before warming, the constituent moments cancel each other exactly. Since they diminish in magnitude at different rates as T is increased to T (c) , their sequential "release" leads to a rich variety of phenomena. A comparison of experimental and theoretical results shows that our simple model semiquantitatively reproduces the major features of the observations on the specimen of Bi:2223/Ag tape.