在铜超导体中超导圆顶之外的铁磁顺序
Tarapada Sarkar1, D S Wei2,3, J Zhang4
1Maryland Quantum Materials Center and Department of Physics, University of Maryland, College Park, MD 20742, USA.
Science (New York, N.Y.)
|May 2, 2020
概括
以前被认为是常规金属的高过量酸盐, 显示出令人惊的四度低铁磁性. 在La2-Ce CuO4 (LCCO) 中的这一发现表明强大的电子相关性影响了这些材料.
科学领域:
- 凝聚物质物理学
- 材料科学
- 量子材料
背景情况:
- 传统的理解认为酸的超导性源于化反铁磁绝缘体.
- 超导圆顶之外的高过量酸盐通常被认为是传统的费米液体金属.
研究的目的:
- 调查超导圆顶之外的高度过度合的酸盐的电子特性.
- 确定电子相关性是否在这些材料的行为中起作用.
主要方法:
- 制造带有电子合的薄膜La2 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- 在低温下测量磁阻,磁化和极性克尔效应 (低于4凯尔文).
主要成果:
- 在高度过量使用的LCCO中,观察四度凯尔文下移动铁磁顺序.
- 证据包括负,异性和歇斯底里磁阻,歇斯底里磁化和极性克尔效应.
- 这些特征是金属中的移动铁磁.
结论:
- 铁磁的出现挑战了传统的看法,即过量使用酸盐是简单的费米液体.
- 这一发现表明,强大的电子相关性显著影响过度合的酸盐,甚至超出了超导相.
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