在固体溶液中最大的化物IrSe2-RhSe2因动离子二元体的不稳定而引起的T(c)
Jiangang Guo1, Yanpeng Qi, Satoru Matsuishi
1Frontier Research Center, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
Journal of the American Chemical Society
|November 29, 2012
概括
我们在一种特定的成分中发现了化 (Ir(0.94-x) Rh(x) Se(2) 中的最佳超导性. 这种增强与较长的二元键和电子转移有关,导致峰值临界温度为9.6K.
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
- 超导性研究 超导性研究
背景情况:
- 超导材料提供了技术潜力,但往往需要特定的条件.
- 调材料组成是优化超导特性的一个关键策略.
研究的目的:
- 在不同的组成中研究Ir{0.94-x) Rh{x) Se{2}的超导行为.
- 阐明这个系统中结构变化和超导性之间的关系.
主要方法:
- 合成了Ir{0.94-x) Rh{x) Se{2}样本,其中"x"的系统变化.
- 测量电阻力以确定超导的临界温度 (T (c)).
- 结构分析以将T (c) 与Se-Se键长度和电子结构相关联.
主要成果:
- 对于Ir{0.94-x) Rh{x) Se{2) 超导体,观察到一个圆顶形的T{c) 曲线.
- 在x = 0.36.3时,最大的T (c) (开始) 达到9.6K.
- 这种最佳的T (c) 与最长的Se-Se分离和Se-Se二极体的不稳定性相关.
结论:
- 超导性质的Ir{0.94-x) Rh{x) Se{2) 对Rh兴奋剂非常敏感.
- 结构和电子变化,特别是Se-Se二极体的不稳定和电子转移,对于实现最佳超导性至关重要.
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