实现了de Gennes的绝对超导开关与重金属接口的实现
Hisakazu Matsuki1, Alberto Hijano2,3,4, Grzegorz P Mazur1,5
1Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK.
Nature communications
|July 2, 2025
概括
研究人员开发了一种新的磁器件,可以打开和关闭超导电. 铁磁/超导体/铁磁结构中的这种"绝对切换"效应可以实现低功耗电子.
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
- 这就是Spintronics.
背景情况:
- 超导开关为低功耗电子产品提供了潜力.
- 之前的铁磁/超导体/铁磁 (F/S/F) 结构显示了超导体临界温度 (Tc) 的有限变化,具有不同的磁对齐.
- 这限制了这些设备的实际应用.
研究的目的:
- 研究一种新的F/S/F结构,以加强对超导的控制.
- 为了实现实际超导交换机应用中Tc的显著转变.
- 探索强大的磁性近距离效应对设备功能的潜力.
主要方法:
- 制造EuS/Au/Nb/EuS结构,其中EuS是一种绝缘铁磁体,Nb是一种超导体,Au是一种重金属.
- 在不同磁化方向下 (平行和反平行) 测量超导的临界温度 (Tc).
- 在EuS/Au接口上的自旋混合导电性的表征.
主要成果:
- 证明了"绝对切换"效应,其中超导率被灭到20mK以实现并行磁化.
- 实现了接近1的ΔTc/Tc,AP比率,明显超过了之前的结果.
- 确定了EuS/Au接口上的相当大的自旋混合电导率是强大的磁性近距离效应的关键因素.
结论:
- 通过磁性切换,EuS/Au/Nb/EuS结构使超导能得到前所未有的控制.
- 观察到的"绝对开关"效应释放了F/S/F设备在低功耗电子产品中的潜力.
- 这项工作为先进的自旋电子和超导应用铺平了道路.
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