在UTe2中超导的反铁磁自旋波动的共振
Chunruo Duan1, R E Baumbach2,3, Andrey Podlesnyak4
1Department of Physics and Astronomy, Rice Center for Quantum Materials, Rice University, Houston, TX, USA.
Nature
|December 23, 2021
概括
在UTe2中超导与磁性激发有关,这表明反铁磁自旋波动可能会诱导这个拓超导体的自旋三重组合或指示一个自旋单子组件.
科学领域:
- 凝聚物质物理学
- 材料科学
- 量子材料
背景情况:
- 在临界温度 (Tc) 下,库珀电子对在没有电阻的情况下产生超导性.
- 大多数超导体表现出自旋单元库珀对 (S=0),但自旋三元对 (S=1) 对拓状态和量子计算至关重要.
- 接近铁磁 (FM) 不稳定的基材料是自旋三极超导的首要候选者,UTe2被确定为潜在的性自旋三极拓超导体.
研究的目的:
- 为了研究UTe2中超导的磁性激发.
- 确定旋转波动 (FM和反铁磁 (AF)) 在UTe2的非传统超导性中的作用.
- 探索UTe2中的配对机制,特别是它是否涉及自旋三位数或自旋单位数库珀对.
主要方法:
- 使用不弹性中子散射 (INS) 来探测UTe2中的磁刺激.
- 这项研究重点关注Brillouin区域边界附近的磁性激发.
- 对观察到的磁激发进行了分析,称为共振.
主要成果:
- 在UTe2与其超导性相结合时,观察到一种强烈的磁激发,即共振.
- 这种共振在Brillouin区域边界附近被发现.
- 这种共振的存在,通常在AF不稳定性附近的自旋单点超导体中见到,在UTe2中是意想不到的.
结论:
- 在UTe2中对共振的观察表明,反铁磁自旋波动可能会诱导自旋三联.
- 另外,这些发现表明UTe2中的电子配对可能具有自旋单子元件.
- 这一发现挑战了现有的范式,并为了解非传统的超导和拓材料开辟了新的途径.
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