在 LaFeAsO0.89F0.11 中的双带超导在非常高的磁场下
F Hunte1, J Jaroszynski, A Gurevich
1National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA. hunte@asc.magnet.fsu.edu
Nature
|May 30, 2008
概括
研究人员研究了在高磁场中的LaFeAsO{0.89) F{0.11) 超导体. 他们发现一个显著增强的上临界场,表明一个新类高场超导体.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 超导电性 超导电性 超导电性
背景情况:
- 最近合成的LaFeAsO{0.89) F{0.11) 超导体,其T{c) ~26K.
- 在相关的oxypnictides中发现更高的过渡温度 (高达52K).
- 对LnOTMPn化合物的非传统超导机制感兴趣.
研究的目的:
- 为了研究LaFeAsO{0.89) F{0.11}的高磁场行为.
- 要确定这个超导体的上临界场 (B(c2).
- 为了将其性能与其他已知的超导体进行比较.
主要方法:
- 在高磁场 (高达45 T) 的电阻测量.
- 对上临界场 (B,C2) 和其温度依赖性的分析.
- 将外推到零度温度以确定B(c2)(0).
主要成果:
- 观察到LaFeAsO (0.89) F (0.11) 中上临界场 (B) (c2) 的显著增强.
- 推断出的B (c2) (0) 值大约为63-65 T,超过了对磁极限.
- B) c2) 值超过了Nb) 3Sn,MgB) 2和Chevrel阶段的值.
结论:
- LaFeAsO{0.89) F{0.11) 代表了一类新的高场超导体.
- 与许多传统超导体相比,这些oxypnictides表现出优越的高场性能.
- 超出100 T基准的潜力,这是高T (c) 氧化铜所设定的.
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