在超导体YBa2Cu3O7中,一个不寻常的相位过渡到第二个液体旋相位
F Bouquet1, C Marcenat, E Steep
1Département de Recherche Fondamentale sur la Matière Condensée, Service de Physique, Magnétisme et Supraconductivité, CEA-Grenoble, 38054, Grenoble, France. Frederic_Bouquet@Yahoo.Com
Nature
|May 25, 2001
概括
研究人员研究了氧化铜 (YBa2Cu3O7) 超导体中的 vortex 阶段. 他们发现了临界点以上的可逆的第二阶段过渡,这表明了新的流液相.
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:
- 超导体允许磁场通过流透,影响电阻.
- 在高温超导体中,旋可以从固态过渡到液态,导致电阻.
- 氧化铜 (YBa2Cu3O7) 中融化的旋的临界点和热力学性质尚不清楚.
研究的目的:
- 为了阐明和铜氧化物 (YBa2Cu3O7) 超导体的相位图.
- 为了研究临界点附近和以上化的热力学性质.
- 描述在高磁场下发生的相位过渡.
主要方法:
- 测量特定热量的方法.
- 磁化测量. 磁化的测量.
- 探索相位图的探测到26特斯拉.
主要成果:
- 乙和铜氧化物 (YBa2Cu3O7) 的相位图被确定为26 T.
- 在临界点以上发现了可逆的第二阶段过渡.
- 高温阶段表现出较低的对称性,与理论预测保持一致.
结论:
- 这项研究建立了相位图,并揭示了YBa2Cu3O7.7在状态中的第二阶段过渡.
- 这些发现支持了对过渡到第二次流液相的理论预测.
- 这项研究阐明了高温超导体在强磁场下的复杂相位行为.
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