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arXiv · 2509.12061

Radio-frequency charge detection on graphene electron-hole double quantum dots

Katrin Hecker·Samuel Möller·Hubert Dulisch·Şiyar Duman·Leon Stecher·Lucca Valerius·Tobias Deußen·Saketh Ravuri·Kenji Watanabe·Takashi Taniguchi·Florian Libisch·Christian Volk·Christoph Stampfer
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Abstract

High-fidelity detection of charge transitions in quantum dots (QDs) is a key ingredient in solid state quantum computation. We demonstrate high-bandwidth radio-frequency charge detection in bilayer graphene quantum dots (QDs) using a capacitively coupled quantum point contact (QPC). The device design suppresses screening effects and enables sensitive QPC-based charge readout. The QPC is arranged to maximize the readout contrast between two neighboring, coupled electron and hole QDs. We apply the readout scheme to a single-particle electron-hole double QD and demonstrate time-resolved detection of charge states as well as magnetic field dependent tunneling rates. This promises a high-fidelity readout scheme for individual spin and valley states, which is important for the operation of spin, valley or spin-valley qubits in bilayer graphene.

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Katrin Hecker, Samuel Möller, Hubert Dulisch, Şiyar Duman, Leon Stecher, Lucca Valerius, Tobias Deußen, Saketh Ravuri, Kenji Watanabe, Takashi Taniguchi, Florian Libisch, Christian Volk, Christoph Stampfer. 2025-09-15. Radio-frequency charge detection on graphene electron-hole double quantum dots. https://doi.org/10.1021/acs.nanolett.5c04648

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