Recently, proximity-induced spin-orbit coupling (SOC) has been observed in heterostructures consisting of monolayer graphene (ML-G) and transition metal dichalcogenides (TMDCs), such as ${\mathrm{WSe}}_2$. Successful tuning of SOC in graphene/${\mathrm{WSe}}_2$ heterostructures by applying mechanical pressure and electric fields was also demonstrated in previous studies. In addition, theoretical calculations predicted a strong dependence of the proximity-induced SOC on the twist angle between graphene and TMDC. Here, we put these predictions to experimental test in $\mathrm{ML}\text{−}\mathrm{G}/\mathrm{ML}\text{−}{\mathrm{WSe}}_2/\mathrm{hBN}$-heterostructures, where the twist angle is determined by aligning fractured edges, and by crystallographic etching of graphene. By performing weak anti-localization measurements, we determine the strength of the Rasbha-type SOC (${\lambda }_{\mathrm{R}}$) and the valley-Zeeman-type SOC (${\lambda }_{\mathrm{VZ}}$). Our experiments confirm a strong twist-angle dependence of the proximity-induced SOC in agreement with theoretical predictions. Finally, we demonstrate the tunability of the SOC strength via mechanical pressure, which is in agreement with earlier findings.

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• Spin-orbit coupling
• Twistronics
• Graphene
• Transition metal dichalcogenides
• Hall bar
• Pressure techniques