Confining electrons in twisted and proximity-coupled bilayer graphene

Gate-defined quantum dots in bilayer graphene-based van der Waals (vdW) heterostructures offer a powerful route to implement spin and valley qubits and to study correlated electron states and proximity coupling in two dimensions. Building on recent progress in bilayer graphene (BLG), we extend electrostatic confinement to more complex vdW systems, including BLG proximity-coupled to transition metal dichalcogenides (TMDs) [1] and twisted bilayer graphene (tBLG) near the magic angle [2]. These hybrid structures combine the excellent tunability of BLG with proximity-induced or twist-angle dependent band modifications, allowing exploration of spin–orbit gaps, valley-dependent transport, and short-range electron–electron interactions. Using advanced multi-gate architectures and low-temperature quantum transport, we investigate how electrostatic potentials confine carriers and modify their internal degrees of freedom. Our results open new opportunities for realizing spin-qubit operation and potentially light–matter coupling schemes in engineered 2D quantum devices based on graphene heterostructures.

[1] H. Dulisch, D. Emmerich, E. Icking, K. Hecker, S. Möller, L. Müller, K. Watanabe, T. Taniguchi, C. Volk, and C. Stampfer, Nano Lett. 25, 10549 (2025)

[2] A. Rothstein, A. Fischer, A. Achtermann, E. Icking, K. Hecker, L. Banszerus, M. Otto, S. Trellenkamp, F. Lentz, K. Watanabe, T. Taniguchi, B. Beschoten, R. J. Dolleman, D. M. Kennes, and C. Stampfer, Nano Lett. 25, 6429 (2025)