2026-07-23 東北大学
図1. (a) 今回の実験で用いた酸化亜鉛デバイスのゲート電極構造。(b) 少数電子二重量子ドットの形成を示す電荷状態安定図。
＜関連情報＞
- https://www.tohoku.ac.jp/japanese/2026/07/press20260723-03-dot.html
- https://journals.aps.org/prapplied/abstract/10.1103/mnt5-s859
無線周波数反射率測定法による少数電子ZnO二重量子ドットの電荷検出 Charge sensing of few-electron ZnO double quantum dots probed by radio-frequency reflectometry
Kosuke Noro, Motoya Shinozaki, Yusuke Kozuka, Koichi Baba, Kazuma Matsumura, Yoshihiro Fujiwara, Takeshi Kumasaka, Atsushi Tsukazaki, Masashi Kawasaki et al.
Physical Review Applied Published: 21 July, 2026
DOI: https://doi.org/10.1103/mnt5-s859
Abstract
Zinc oxide (ZnO) has garnered much attention as a promising material for quantum devices due to its unique characteristics. To utilize the potential of ZnO for quantum devices, the development of fundamental technological elements such as high-speed readout and charge sensing capabilities has become essential. In this study, we address these challenges by demonstrating radio-frequency (rf) reflectometry and charge sensing in ZnO quantum dots, thus advancing the potential for qubit applications. A device is fabricated on a high-quality ZnO heterostructure, featuring gate-defined target and sensor quantum dots. The sensor dot, integrated into an rf resonator circuit, enables the detection of single-electron charges in the target dots. Using this setup, we observe the rf-detected charge stability diagram indicating the formation of few-electron double quantum dots and provide the first benchmark of the bandwidth, sensitivity, and readout fidelity of rf reflectometry.
