Charge sensing of few-electron ZnO double quantum dots probed by radio-frequency reflectometry
Phys. Rev. Applied 26, 014065 – 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.
