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arXiv · 2404.09910

Tuning confined states and valley g-factors by quantum dot design in bilayer graphene

Dennis Mayer·Angelika Knothe
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Abstract

Electrostatically confined quantum dots in bilayer graphene have shown potential as building blocks for quantum technologies. To operate the dots, e.g., as qubits, a precise understanding and control of the confined states and their properties is required. Herein, a large-scale numerical characterization of confined quantum states in bilayer graphene dots is performed over an extensive range of gate-tunable parameters such as the dot size, depth, shape, and the bilayer graphene gap. The dot states' orbital degeneracy, wave function distribution, and valley g-factor are established and the parametric dependencies to achieve different regimes are provided. It is found that the dot states are highly susceptible to gate-dependent confinement and material parameters, enabling efficient tuning of confined states and valley g-factor modulation by quantum dot design.

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Dennis Mayer, Angelika Knothe. 2024-04-15. Tuning confined states and valley g-factors by quantum dot design in bilayer graphene. https://doi.org/10.1002/pssb.202300395

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