Tunable Pure Spin Supercurrents and the Demonstration of Their Gateability in a Spin-Wave Device
Tunable Pure Spin Supercurrents and the Demonstration of Their Gateability in a Spin-Wave Device
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DOI：
10.1103/physrevx.10.031020
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发表时间：
2020-07-27
影响因子：
12.5
通讯作者：
Robinson, Jason W. A.
中科院分区：
文献类型：
--
作者：
Jeon, Kun-Rok;Montiel, Xavier;Robinson, Jason W. A.
最近的铁磁共振实验和铂/Nb/Ni8Fe2邻近耦合结构的理论有力地表明，铂中的自旋-轨道耦合(SOC)和Ni8Fe2中的磁场交换是在Nb中产生纯自旋超流通道的基本成分。通过用铂代替垂直磁化的铂/钴/铂自旋汇，我们证明了SOC的作用，并证明了纯自旋超流的泵浦效率可以通过控制Co的磁化方向来调节。通过在Nb和铂/(Co/铂)自旋汇之间插入具有弱自旋超电流的铜隔离层，我们还证明了Rashba型SOC是形成和传输纯自旋超流的关键。最后，通过在单个多层结构中设计这些性质，我们展示了一个原型超导自旋波器件，在该器件中，横向自旋波的传播可以通过打开或关闭Nb中垂直的纯自旋超流通道来实现。
Recent ferromagnetic resonance experiments and theory of Pt/Nb/Ni8Fe2 proximity-coupled structures strongly suggest that spin-orbit coupling (SOC) in Pt in conjunction with a magnetic exchange field in Ni8Fe2 are the essential ingredients to generate a pure spin supercurrent channel in Nb. Here, by substituting Pt for a perpendicularly magnetized Pt/Co/Pt spin sink, we are able to demonstrate the role of SOC and show that pure spin supercurrent pumping efficiency across Nb is tunable by controlling the magnetization direction of Co. By inserting a Cu spacer with weak SOC between Nb and Pt/ (Co/Pt) spin sink, we also prove that Rashba-type SOC is key for forming and transmitting pure spin supercurrents across Nb. Finally, by engineering these properties within a single multilayer structure, we demonstrate a prototype superconductor spin-wave device in which lateral spin-wave propagation is gateable via the opening or closing of a vertical pure spin supercurrent channel in Nb.