Cr/Fe and Pt/Co spin-mixer interfaces for spin-aligned triplet Cooper pair creation

超导体和铁磁体之间的界面承载着丰富的物理现象，可以在低能计算中找到应用。这就是超导自旋电子学这一新兴领域的目标。这项工作的重点是制造纳米柱约瑟夫森结，其中包括一个铁磁层和一个自旋混合器，以研究超电流的远程三重态分量（LRTC）的产生。预计在Cr/Fe界面处会产生自旋玻璃，这提供了产生LRTC所需的磁不均匀性。最近有人提出，自旋轨道耦合（SOC）可以取代磁不均匀性在三重态相互转换中的作用[2,3]；为了研究这一点，我们制造了具有Pt/Co接口的器件。铂原子序数高，界面反转对称性破坏，是纯Rashba型荷电晶体。此外，实验还表明，超导体与大块SOC材料的界面可以增强自旋输运；因此，探索了铁/铬基器件与附加薄铂层的组合Robinson， J. W. A, Banerjee， N.和Blamire， M. G. 104505,1 -4（2014）。[10]柏格里特，F. S., Tokatly， I. V.物理学家。生态学报，39(1)（2014）。bbb Jacobsen， S., Kulagina， I.和Linder， J. Sci.。6:23926 (2015).[4]全,K.-R。et al。高分子学报，17,499（2018）。

Interfaces between superconductors and ferromagnets host rich physical phenomena which may find applications in low-energy computing. This is the aim of the emerging field of superconducting spintronics. This work focuses on the fabrication of nanopillar Josephson junctions which include a ferromagnetic layer and a spin-mixer in order to investigate the generation of a long-range triplet component (LRTC) of the supercurrent. A spin-glass is predicted to arise at a Cr/Fe interface [1], which provides the magnetic inhomogeneity required to generate a LRTC. It has recently been proposed that spin-orbit coupling (SOC) may substitute the role of the magnetic inhomogeneity in interconverting the triplet states [2,3]; to investigate this we fabricate devices with Pt/Co interfaces. The SOC arises from the high atomic number of Pt and broken inversion symmetry at its interfaces, and is of pure Rashba type. Furthermore, it has been shown experimentally that interfacing a superconductor with a large SOC material enhances spin transport through the superconductor [4]; hence the combination of Fe/Cr based devices with an additional thin Pt layer is explored.[1] Robinson, J. W. A., Banerjee, N., & Blamire, M. G. 104505, 1-4 (2014). [2] Bergeret, F. S., & Tokatly, I. V. Phys. Rev. B 89(13), 1-13 (2014). [3] Jacobsen, S., Kulagina, I., & Linder, J. Sci. Rep. 6:23926 (2015).[4] Jeon, K.-R. et al. Nat. Mater. 17, 499 (2018).