Dulisch H, Emmerich D, Icking E, Hecker K, Möller S, Müller L, Watanabe K, Taniguchi T, Volk C, Stampfer C
JARA-FIT and 2nd Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany.
Peter Grünberg Institute (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany.
Nano Lett. 2025 Jul 2;25(26):10549-10555. doi: 10.1021/acs.nanolett.5c02229. Epub 2025 Jun 18.
We report on the investigation of proximity-induced spin-orbit coupling (SOC) in a heterostructure of bilayer graphene (BLG) and tungsten diselenide (WSe). A BLG quantum dot (QD) in the few-particle regime acts as a sensitive probe for induced SOC. Finite bias and magnetotransport spectroscopy measurements reveal a significantly enhanced SOC that decreases with the applied displacement field, distinguishing it from pristine BLG. Furthermore, our measurements demonstrate a reduced valley factor at larger displacement fields, consistent with weaker lateral confinement of the QD. Our findings show evidence of the influence of WSe across BLG layers, driven by reduced real-space confinement and increased layer localization of the QD states on the BLG layer distant to the WSe at higher displacement fields. This study demonstrates the electrostatic tunability of the spin-orbit gap in BLG/WSe heterostructures, which is especially relevant for the field of spintronics and future spin qubit control in BLG QDs.
我们报告了对双层石墨烯（BLG）和二硒化钨（WSe）异质结构中近邻诱导自旋轨道耦合（SOC）的研究。处于少粒子 regime 的 BLG 量子点（QD）作为诱导 SOC 的灵敏探针。有限偏置和磁输运光谱测量揭示了显著增强的 SOC，其随施加的位移场减小，这使其有别于原始 BLG。此外，我们的测量表明在较大位移场处谷因子降低，这与 QD 的较弱横向限制一致。我们的发现表明，在较高位移场下，由于实空间限制减小以及 QD 态在远离 WSe 的 BLG 层上的层定位增加，WSe 对 BLG 各层产生了影响。这项研究证明了 BLG/WSe 异质结构中自旋轨道间隙的静电可调性，这对于自旋电子学领域以及 BLG QD 中未来的自旋量子比特控制尤为重要。
