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arXiv · 2105.04832

4.2 K Sensitivity-Tunable Radio Frequency Reflectometry of a Physically Defined P-channel Silicon Quantum Dot

Sinan Bugu·Shimpei Nishiyama·Kimihiko Kato·Yongxun Liu·Shigenori Murakami·Takahiro Mori·Thierry Ferrus·Tetsuo Kodera
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Abstract

We demonstrate the measurement of p-channel silicon-on-insulator quantum dots at liquid helium temperatures by using a radio frequency (rf) reflectometry circuit comprising of two independently tunable GaAs varactors. This arrangement allows observing Coulomb diamonds at 4.2\,K under nearly best matching condition and optimal signal-to-noise ratio. We also discuss the rf leakage induced by the presence of the large top gate in MOS nanostructures and its consequence on the efficiency of rf-reflectometry. These results open the way to fast and sensitive readout in multi-gate architectures, including multi-qubit platforms.

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Sinan Bugu, Shimpei Nishiyama, Kimihiko Kato, Yongxun Liu, Shigenori Murakami, Takahiro Mori, Thierry Ferrus, Tetsuo Kodera. 2021-05-11. 4.2 K Sensitivity-Tunable Radio Frequency Reflectometry of a Physically Defined P-channel Silicon Quantum Dot. https://doi.org/10.1038/s41598-021-99560-x

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