Spin-Orbit Coupling-Driven Superconducting Spintronics

自旋轨道耦合驱动的超导自旋电子学

• 批准号: EP/S016430/1
• 负责人: Niladri Banerjee
• 金额: $ 23.75万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FS016430%2F1
• 关键词: Spin; Orbit; Coupling; Driven; Superconducting

Ferromagnetism arises from parallel alignment of electron spins in a material and is much stronger than conventional singlet superconductivity resulting from the pairing of electrons with opposite spins. Therefore, the coupling or the proximity effect between superconductivity and ferromagnetism is short-ranged and is restricted to only a few nanometres from the interface of the two materials.However, in the last ten years surprising results from the interaction of superconductivity and ferromagnetism has challenged this conventional picture. At suitably engineered superconductor/ferromagnet interfaces, it is possible to generate superconductivity mediated by equal spin-paired electrons (triplet pairs) enabling a superconductor to carry a dissipationless current with a non-zero spin. The finite spin-polarisation and the zero dissipation integrates the rich potentials of spin based electronics (spintronics) and superconducting electronics into a rich new field of superconducting spintronics. Although attractive both fundamentally and in its reach for potential applications, generating triplet pairs at superconductor/ferromagnet interfaces require prohibitively complex magnetic structures.Strikingly, a dramatic simplification can be achieved by incorporating spin-orbit coupling in superconductor/ferromagnet heterostructures. Our recent experiments have indicated that using heavy-metals at superconductor/ferromagnet interfaces, it is possible to generate and control triplet pairs using a simple homogeneous ferromagnet. This not only radically simplifies structures used in superconducting spintronics but opens-up the possibility to study a new class of effects predicted to occur due to the coexistence of superconductivity, ferromagnetism and spin-orbit coupling.In this proposal, we will establish our understanding by focusing on three key areas: understanding the role of the materials and interfaces, maximise the triplet generation efficiency and finally, demonstrate a functional device working on triplet generation and control using spin-orbit coupling. With these objectives, we hope to achieve i) spin-orbit coupling as an efficient source and controlling factor for triplets thereby making superconducting spintronics ideas practically feasible ii) a functional device that is far simpler than any previously designed and serves as a blue-print for future device designs with radically new functionalities.

铁磁性产生于材料中电子自旋的平行排列，并且比由具有相反自旋的电子配对产生的常规单重态超导性强得多。因此，超导和铁磁性之间的耦合或邻近效应是短程的，并且仅限于两种材料界面的几纳米范围内。然而，在过去的十年中，超导和铁磁性相互作用的惊人结果挑战了这一传统的观点。在适当设计的超导体/铁磁界面上，可以产生由等自旋配对电子（三重态对）介导的超导性，使超导体能够携带具有非零自旋的无耗散电流。有限自旋极化和零耗散将自旋电子学和超导电子学的丰富潜能整合为超导自旋电子学的一个新领域。尽管在超导体/铁磁体界面产生三重态对在理论上和应用上都很有吸引力，但它需要极其复杂的磁性结构，而在超导体/铁磁体异质结构中引入自旋-轨道耦合可以大大简化这一过程。我们最近的实验表明，在超导体/铁磁体界面处使用重金属，使用简单的均匀铁磁体来产生和控制三重态对是可能的。这不仅从根本上简化了超导自旋电子学中使用的结构，而且开辟了研究一类新效应的可能性，这些效应预计将由于超导性，铁磁性和自旋轨道耦合的共存而发生。在这个提议中，我们将通过关注三个关键领域来建立我们的理解：理解材料和界面的作用，最大化三重态产生效率，最后，演示了一个功能性的装置，利用自旋轨道耦合产生和控制三重态。有了这些目标，我们希望实现i）自旋轨道耦合作为三重态的有效来源和控制因素，从而使超导自旋电子学的想法实际可行ii）功能器件比以前设计的任何器件都要简单得多，并作为未来具有全新功能的器件设计的蓝图。

项目成果

Strain driven emergence of topological non-triviality in YPdBi thin films.

• DOI: 10.1038/s41598-021-86936-2
• 发表时间: 2021-04-06
• 期刊: Scientific reports
• 影响因子: 4.6
• 作者: Bhardwaj V;Bhattacharya A;Srivastava S;Khovaylo VV;Sannigrahi J;Banerjee N;Mani BK;Chatterjee R
• 通讯作者: Chatterjee R

Colloquium: Spin-orbit effects in superconducting hybrid structures

研讨会：超导混合结构中的自旋轨道效应

• DOI: 10.48550/arxiv.2210.03549
• 发表时间: 2022
• 作者: Amundsen M

Superconductivity-induced change in magnetic anisotropy in epitaxial ferromagnet-superconductor hybrids with spin-orbit interaction

• DOI: 10.1103/physrevb.102.020405
• 发表时间: 2020-07-15
• 期刊: PHYSICAL REVIEW B
• 影响因子: 3.7
• 作者: Gonzalez-Ruano, Cesar;Johnsen, Lina G.;Aliev, Farkhad G.
• 通讯作者: Aliev, Farkhad G.

Large electrocaloric effect in lead-free ferroelectric Ba0.85Ca0.15Ti0.9Zr0.1O3 thin film heterostructure

• DOI: 10.1063/5.0039143
• 发表时间: 2021-02
• 期刊: APL Materials
• 影响因子: 6.1
• 作者: A. Barman;Subhashree Chatterjee;Canlin Ou;Yau Yau Tse-Yau;N. Banerjee;S. Kar‐Narayan;A. Datta;D. Mu

Long-ranged triplet supercurrent in a single in-plane ferromagnet with spin-orbit coupled contacts to superconductors

• DOI: 10.1103/physrevb.100.224519
• 发表时间: 2019-12-27
• 期刊: PHYSICAL REVIEW B
• 影响因子: 3.7
• 作者: Eskilt, Johannes R.;Amundsen, Morten;Linder, Jacob
• 通讯作者: Linder, Jacob