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arXiv · 2502.15239

RFSoC-based radio-frequency reflectometry in gate-defined bilayer graphene quantum devices

Motoya Shinozaki·Tomoya Johmen·Aruto Hosaka·Takumi Seo·Shunsuke Yashima·Akitomi Shirachi·Kosuke Noro·Shoichi Sato·Takashi Kumasaka·Tsuyoshi Yoshida·Tomohiro Otsuka
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Abstract

Quantum computers require both scalability and high performance for practical applications. While semiconductor quantum dots are promising candidates for quantum bits, the complexity of measurement setups poses an important challenge for scaling up these devices. Here, radio-frequency system-on-chip (RFSoC) technology is exepcted for a promising approach that combines scalability with flexibility. In this paper, we demonstrate RF reflectometry in gate-defined bilayer graphene quantum devices using RFSoC-based measurement architecture. By controlling the confinement strength through gate voltages, we achieve both Fabry-P\'erot interferometer and quantum dot operations in a single device. Although impedance matching conditions currently limit the measurement sensitivity, we identify pathways for optimization through tunnel barrier engineering and resonator design. These results represent a step toward integrating high-bandwidth measurements with scalable quantum devices.

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Motoya Shinozaki, Tomoya Johmen, Aruto Hosaka, Takumi Seo, Shunsuke Yashima, Akitomi Shirachi, Kosuke Noro, Shoichi Sato, Takashi Kumasaka, Tsuyoshi Yoshida, Tomohiro Otsuka. 2025-02-21. RFSoC-based radio-frequency reflectometry in gate-defined bilayer graphene quantum devices. https://doi.org/10.35848/1882-0786%2Fade6c2

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