在 (Ca4Al2O6) ((Fe2As2) 和 (Ca4Al2O6) ((Fe2P2) 超导体之间的固体溶液中超导性的消失
Parasharam M Shirage1, Kunihiro Kihou, Chul-Ho Lee
1National Institute of Advanced Industrial Science and Technology (AIST), Central-2, 1-1-1 Umezono, Tsukuba, Ibaraki-305 8568, Japan. paras.shirage@gmail.com
Journal of the American Chemical Society
|September 1, 2012
概括
合金铁基超导体 (Ca4Al2O6) ((Fe2As2) 和 (Ca4Al2O6) ((Fe2P2) 在固体溶液中抑制了超导性. 电阻异常表明这种抑制的磁性或结构起源.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 研究矿类铁基超导体对于理解高温超导性至关重要.
- 铁化物和相关材料的化学组成和超导特性之间的相互作用是一个关键的研究领域.
研究的目的:
- 检查矿类铁基超导体 (Ca4Al2O6) ((Fe2As2) 和 (Ca4Al2O6) ((Fe2P2)) 合金的作用.
- 确定固体溶液 (Ca4Al2O6) ((Fe2 ((As1-xPx) 2) 的超导特性,并将其相位图与其他铁基超导体进行比较.
主要方法:
- 合成和特征的固体测量化合物 (Ca4Al2O6) ((Fe2As2) 和 (Ca4Al2O6) ((Fe2P2).2) 的合成和特征.
- 准备和测量固体溶液 (Ca4Al2O6) ((Fe2 ((As1-xPx) 2) 的电电阻,在广泛的P替代范围 (x = 0.50到0.95) 中进行测量.
主要成果:
- 固态测量化合物的临界温度 (Tc) 分别为28K和17K.
- 固体溶液对于x在0.50到0.95之间没有超导,因此与其他铁基超导体相比,它具有独特的相位图.
- 在非超导体固体溶液中观察到50-100K之间的电阻异常.
结论:
- (Ca4Al2O6) ((Fe2As2) 和 (Ca4Al2O6) ((Fe2P2) 的合金导致在广泛的组成范围内抑制超导.
- 观察到的电阻异常表明,超导的抑制可能是由磁性和/或结构秩序驱动的,类似于其他铁基超导体家族的母化合物.
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