在高温超导体YBa2Cu3Oy中的磁场诱导的电荷条纹顺序
Tao Wu1, Hadrien Mayaffre, Steffen Krämer
1Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UJF-UPS-INSA, 38042 Grenoble, France.
Nature
|September 9, 2011
概括
高磁场诱导YBa(2)Cu(3)O(y的氧化铜平面中的电荷顺序,揭示了高过渡温度超导体中电荷顺序的内在趋势. 这一发现澄清了超导和电子秩序之间的竞争.
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:
- 铜氧化物中的高过渡温度 (Tc) 超导性与CuO(2) 平面中的电子电荷有关.
- 铜氧化物中潜在的电荷顺序的存在及其与超导性的关系仍然存在争议.
- 之前的研究表明,超导性在YBa(2)Cu(3)O(y) 中与自旋顺序竞争,而不是电荷顺序.
研究的目的:
- 调查在强磁场下的YBa(2) Cu(3) O(y) 在CuO(2) 平面中的电子秩序的存在和性质.
- 要确定YBa(2)Cu(3)O(y) 中是否存在充电顺序,以及它与超导性的关系.
- 为了澄清超导和电子订单现象之间的竞争.
主要方法:
- 核磁共振 (NMR) 测量对YBa{2) Cu{3) O{y}进行了测量.
- 强大的磁场被应用来破坏超导和探测电子秩序.
- 分析的重点是检测电荷密度的静态,单向调制.
主要成果:
- 发现高磁场在YBa(2) Cu(3) O(y) 的CuO(2) 平面中诱导静态的,单向的电荷顺序.
- 这种诱导充电顺序发生在没有伴随的旋转顺序的情况下.
- 观察到的电荷顺序是4a周期调制,类似于其他氧化铜的条纹顺序,并且随着超导率的减少而出现.
结论:
- 电荷顺序是高Tc铜氧化物中超导平面的内在倾向,即使在YBa(2) Cu(3) O(y) 等清洁样品中也是如此.
- 诱导的电荷顺序打破了转换对称性,并解释了以前的量子振荡结果.
- 这些发现表明,超导和充电顺序之间存在竞争,特别是在特定的兴奋剂水平附近 (例如1/8洞兴奋剂).
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