题名 |
Physical Properties of the Weak-Ferromagnetic Superconductor RuSr2EuCu2O8 |
作者 |
B. C. Chang;C. Y. Yang;H. C. Ku;J. C. Ho;C. B. Tsai;Y. Y. Chen;D. C. Ling |
关键词 | |
期刊名称 |
Chinese Journal of Physics |
卷期/出版年月 |
47卷4期(2009 / 08 / 01) |
页次 |
529 - 539 |
内容语文 |
英文 |
英文摘要 |
Similar to the optimal-doped, weak-ferromagnetic (WFM induced by canted antiferromagnetism, T(subscript Curie)=131K) and superconducting (T(subscript c)=56K) RuSr2GdCu2O8, underdoped RuSr2EuCu2O8 (T(subscript Curie)=133K, T(subscript c)=36K) also exhibited a spontaneous vortex state (SVS) between 16K and 36K. The low field (±20G) superconducting hysteresis loop indicates a weak and narrow Meissner state region of average lower critical field B(superscript ave subscript cl) (T)=B(superscript ave subscript cl) (0)[1-(T/T(subscript SVS))^2], with B(superscript ave subscript cl) (0)=7G and T(subscript SVS)=16K. The vortex melting transition (T(subscript melting)=21K) below T(subscript c), obtained from the broad resistivity drop and the onset of the diamagnetic signal, indicates a vortex liquid region due to the coexistence and interplay between superconductivity and the WFM order. No visible jump in specific heat was observed near T(subscript c) for Eu-and Gd-compounds. Finally, with the baseline from the nonmagnetic Eu-compound, the specific heat data analysis confirms the magnetic entropy associated with antiferromagnetic ordering of Gd^3+(J=S=7/2) at 2.5K to be close to N(subscript A)k ln 8, as expected. |
主题分类 |
基礎與應用科學 >
物理 |
被引用次数 |
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