Bangar Himanshu, Kumar Akash, Chowdhury Niru, Mudgal Richa, Gupta Pankhuri, Yadav Ram Singh, Das Samaresh, Muduli Pranaba Kishor
Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
Department of Physics, University of Gothenburg, Gothenburg 412 96, Sweden.
ACS Appl Mater Interfaces. 2022 Sep 14;14(36):41598-41604. doi: 10.1021/acsami.2c11162. Epub 2022 Sep 2.
Spin-to-charge conversion is an essential requirement for the implementation of spintronic devices. Recently, monolayers (MLs) of semiconducting transition-metal dichalcogenides (TMDs) have attracted considerable interest for spin-to-charge conversion due to their high spin-orbit coupling and lack of inversion symmetry in their crystal structure. However, reports of direct measurement of spin-to-charge conversion at TMD-based interfaces are very much limited. Here, we report on the room-temperature observation of a large spin-to-charge conversion arising from the interface of NiFe (Py) and four distinct large-area (∼5 × 2 mm) ML TMDs, namely, MoS, MoSe, WS, and WSe. We show that both spin mixing conductance and the Rashba efficiency parameter (λ) scale with the spin-orbit coupling strength of the ML TMD layers. The λ parameter is found to range between -0.54 and -0.76 nm for the four ML TMDs, demonstrating a large spin-to-charge conversion. Our findings reveal that the TMD/ferromagnet interface can be used for efficient generation and detection of spin current, opening new opportunities for novel spintronic devices.
自旋到电荷的转换是实现自旋电子器件的一项基本要求。最近,半导体过渡金属二硫属化物(TMD)的单层(ML)因其高自旋轨道耦合以及晶体结构中缺乏反演对称性,在自旋到电荷的转换方面引起了相当大的关注。然而,基于TMD的界面处自旋到电荷转换的直接测量报告非常有限。在此,我们报告了在室温下对由NiFe(Py)与四种不同的大面积(约5×2毫米)ML TMD(即MoS、MoSe、WS和WSe)界面产生的大量自旋到电荷转换的观测结果。我们表明,自旋混合电导和Rashba效率参数(λ)均与ML TMD层的自旋轨道耦合强度成比例。发现这四种ML TMD的λ参数在-0.54至-0.76纳米之间,表明存在大量的自旋到电荷转换。我们的研究结果表明,TMD/铁磁体界面可用于高效产生和检测自旋电流,为新型自旋电子器件开辟了新机遇。