Two-dimensional (2D) materials are promising candidates for spintronic applications. Maintaining their atomically smooth interfaces during integration of ferromagnetic (FM) electrodes is crucial since conventional metal deposition tends to induce defects at the interfaces. Meanwhile, the difficulties in picking up FM metals with strong adhesion and in achieving conductance match between FM electrodes and spin transport channels make it challenging to fabricate high-quality 2D spintronic devices using metal transfer techniques. Here, we report a solvent-free magnetic electrode transfer technique that employs a graphene layer to assist in the transfer of FM metals. It also serves as part of the FM electrode after transfer for optimizing spin injection, which enables the realization of spin valves with excellent performance based on various 2D materials. In addition to two-terminal devices, we demonstrate that the technique is applicable for four-terminal spin valves with nonlocal geometry. Our results provide a promising future of realizing 2D spintronic applications using the developed magnetic electrode transfer technique.

中文翻译：

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二维自旋电子器件的范德华磁电极转移


二维（2D）材料是自旋电子学应用的有希望的候选材料。在铁磁（FM）电极集成过程中保持原子级光滑的界面至关重要，因为传统的金属沉积往往会在界面处产生缺陷。同时，拾取具有强粘附力的FM金属以及实现FM电极和自旋输运通道之间的电导匹配的困难使得利用金属转移技术制造高质量的2D自旋电子器件具有挑战性。在这里，我们报告了一种无溶剂磁性电极转移技术，该技术采用石墨烯层来协助 FM 金属的转移。它还可以作为转移后 FM 电极的一部分，用于优化自旋注入，从而实现基于各种 2D 材料的具有优异性能的自旋阀。除了两端器件外，我们还证明该技术适用于具有非局部几何形状的四端自旋阀。我们的研究结果为使用开发的磁电极转移技术实现二维自旋电子应用提供了广阔的前景。