Excitation field dependence, frequency dependence and anisotropy of the irreversibility line in MPMG YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7</sub> with Y<sub>2</sub>BaCuO<sub>5</sub> inclusions
M Slaski; L T Sagdahl; L K Heill; K Fossheim; M Murakami; H Fujimoto; N Koshizuka; S Tanaka; M Slaski; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; L T Sagdahl; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; L K Heill; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; K Fossheim; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; M Murakami; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; H Fujimoto; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; N Koshizuka; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway; S Tanaka; Div. of Phys., Norwegian Inst. of Technol., Trondheim, Norway
Журнал:
Superconductor Science and Technology
Дата:
1992-01-01
Аннотация:
Most applications of superconducting materials require high critical current density. Melt-powder-melt-grown (MPMG) YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7</sub> with Y<sub>2</sub>BaCuO<sub>5</sub> inclusions were found to have the highest critical current in bulk to date. The authors report a systematic study of the irreversible behaviour in the MPMG material. The irreversibility line was measured in external fields up to 8 T using an AC susceptibility technique. Large anisotropy of the irreversibility line for different orientations of the field was observed. The frequency dependence was found to be logarithmic in the range 10 to 10<sup>5</sup> Hz. In order to study the excitation field dependence in detail, they applied AC fields from 0.01 G up to 30 G.
149.0Кб