在La(2)CuO(4+y) 中氧间位的无尺度结构组织
Michela Fratini1, Nicola Poccia, Alessandro Ricci
1Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, 00185 Roma, Italy.
Nature
|August 13, 2010
概括
在La(2)CuO(4+y) 超导体中,氧的排序表现出一个碎形分布. 这种复杂的微观结构,带有碎形补充剂,似乎增强了这些材料的高温超导性.
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:
- 过渡金属氧化物的微结构,特别是高过渡温度 (高T) 的氧化铜超导体,是复杂的.
- 氧气间隙或空隙显著影响这些材料的散装性质.
- 众所周知,间隔层中氧气间隙的排序现象会影响过渡温度,而不会改变孔度.
研究的目的:
- 为了研究La(2)CuO(4+y) 高T(c) 超导体中氧介质的结构组织.
- 为了确定复杂系统的特征,在高T (c) 材料中是否存在规模不变的结构组织.
- 探索氧气间位序列和超导功率增强之间的关系.
主要方法:
- 在高T超导体中微结构的分析. La(2) CuO(4+y) 超导体.
- 在La(2) O(2+y) 间隔层中氧气间歇排序的表征.
- 在多邦组织中研究碎形分布模式.
主要成果:
- 在La(2)CuO(4+y) 超导体中氧气间位数的排序显示了碎形分布.
- 这种碎形分布延伸到400微米的最大尺寸.
- 观察到多剂的碎形分布可以增强高温超导性.
结论:
- 在La(2)CuO(4+y) 中氧的间歇排序表现出以前未被发现的碎形组织.
- 这种碎形微观结构与增强的高温超导性有关.
- 这些发现揭示了高T (c) 材料中复杂系统的新方面.
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