超导相图的Na(x) CoO2*1.3H2O的超导相图
R E Schaak1, T Klimczuk, M L Foo
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Nature
|August 2, 2003
概括
在,氧化水的超导性镜像高过渡温度铜氧化物. 它的临界温度 (T ((c)) 取决于电子度,随着低剂量或过量剂量的使用而下降.
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
- 固态化学 固态化学
背景情况:
- 铜氧化物中高过渡温度超导的微观起源是一个关键的研究领域.
- 超导的依赖电子带填充是一个普遍的特征.
- 氧化 (Na(x) CoO2*1.3H2O) 具有超导性,并且与铜氧化物具有结构上的相似性.
研究的目的:
- 为了研究Na(x) CoO2*1.3H2O的超导特性.
- 为了比较Na(x) CoO2*1.3H2O中的超导性与氧化铜超导体的兴奋剂依赖.
主要方法:
- 化学合Na(x) CoO2*1.3H2O以改变和电子度.
- 测量超导的临界温度 (T(c)) 作为兴奋剂水平的函数.
主要成果:
- 在Na (x) CoO2*1.3H2O中的超导性在狭窄的度范围内表现出最佳的T (c).
- 在低兴奋剂和过度兴奋剂方案中,T (c) 降低,反映了在高T (c) 氧化铜中观察到的行为.
- 需要注意的是三角形的氧格子和Na(x) CoO2*1.3H2O的磁性特性.
结论:
- 超导性在Na (x) CoO2*1.3H2O中的兴奋剂依赖性与高T (c) 铜氧化物提供了相似之处.
- 这种化合物可能为涉及合电荷和自旋动态的超导机制提供了洞察力.
- 格子几何和磁性特性的差异表明了这种材料中超导的独特方面.
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