PROXIMITY EFFECTS IN GRAPHENE VAN DER WAALS HETEROSTRUCTURES
Layered van der Waals heterostructures provide a versatile platform for great tunability of electronic properties via proximity effects. Proximitized spin-orbit coupling, exchange interaction, and superconductivity properties in materials that intrinsically lack these properties are of great interest for future nanoelectronics [1,2]. In this talk, we present proximity-induced spin-orbit coupling and exchange interaction in graphene on semiconducting 1H-WSe2 and metallic 1T-TaS2 transition metal dichalcogenides. We use first-principles calculations based on density functional theory and tight-binding modeling of the proximity effects on graphene electronic states. Specifically, we discuss spin patterns in graphene electronic states modified by the charge density wave and ferromagnetism in 1T-TaS2 [3], and their relevance for the generation of spin current and spin-orbit torque. Transition metal iodides encapsulated in graphene [4] represent recently discovered stable structures that provide systems with a novel interplay of proximity-induced spin-orbit coupling and electric polarization.
Proximity effects, graphene, van der Waals heterostructures
This work was supported by the Slovak Academy of Sciences project IMPULZ IM-2021-42 and project FLAG ERA JTC 2021 2DSOTECH, Slovak Research and Development Agency provided under Contract No. APVV-SK-CZ-RD-21-0114 and by the Ministry of Education, Science, Research and Sport of the Slovak Republic provided under Grant No. VEGA 1/0105/20.
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[2] M. Gmitra, J. Fabian, "Proximity Effects in Bilayer Graphene on Monolayer WSe2: Field-Effect Spin Valley Locking, Spin-Orbit Valve, and Spin Transistor", Phys. Rev. Lett. 119, 146401 (2017).
[3] K. Szałowski, M. Milivojević, D. Kochan, and M. Gmitra, "Spin–orbit and exchange proximity couplings in graphene/1T-TaS2 heterostructure triggered by a charge density wave", 2D Materials 10, 025013 (2023).
[4] K. Mustonen, C. Hofer, P. Kotrusz, A. Markevich, M. Hulman, C. Mangler, T. Susi, T. J. Pennycook, K. Hricovini, C. Richter, J. C. Meyer, J. Kotakoski, V. Skákalová, "Toward Exotic Layered Materials: 2D Cuprous Iodide", Advanced Materials 34, 2106922 (2022).