The anomalous mixed state of the C15-Laves phase superconductor : II. History dependence in field-cooled magnetization hysteresis
S B Roy; P Chaddah; Sujeet Chaudhary; S B Roy; Low Temperature Physics Group, Centre for Advanced Technology, Indore 452013, India; P Chaddah; Low Temperature Physics Group, Centre for Advanced Technology, Indore 452013, India; Sujeet Chaudhary; Low Temperature Physics Group, Centre for Advanced Technology, Indore 452013, India
Журнал:
Journal of Physics: Condensed Matter
Дата:
1998-09-21
Аннотация:
=1 We report an unusual history dependence of the field-cooled magnetization in and around the peak-effect regime of the superconducting mixed state of . Such history effects in magnetization are shown to be absent in the peak-effect regime of the high- superconductor Bi-2212. Some qualitative similarities with and at the same time considerable quantitative differences from relatively old studies of the history dependence of the transport critical current density in single-crystal Nb and and amorphous films are examined. Our work indicates that the peak effect in is probably due to a first-order phase transition unlike the peak effect in Bi-2212, and that the latter could be due to a continuous or second-order phase transition. Differences in details of the history effects suggest that the origin of the peak effect in is likely to be different from those for these hard type-II superconductors.
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