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arXiv · 1604.04426

Detection and control of charge states in a quintuple quantum dot

Takumi Ito·Tomohiro Otsuka·Shinichi Amaha·Matthieu R. Delbecq·Takashi Nakajima·Jun Yoneda·Kenta Takeda·Giles Allison·Akito Noiri·Kento Kawasaki·Seigo Tarucha
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Abstract

A semiconductor quintuple quantum dot with two charge sensors and an additional contact to the center dot from an electron reservoir is fabricated to demonstrate the concept of scalable architecture. This design enables formation of the five dots as confirmed by measurements of the charge states of the three nearest dots to the respective charge sensor. The gate performance of the measured stability diagram is well reproduced by a capacitance model.These results provide an important step towards realizing controllable large scale multiple quantum dot systems.

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Takumi Ito, Tomohiro Otsuka, Shinichi Amaha, Matthieu R. Delbecq, Takashi Nakajima, Jun Yoneda, Kenta Takeda, Giles Allison, Akito Noiri, Kento Kawasaki, Seigo Tarucha. 2016-04-15. Detection and control of charge states in a quintuple quantum dot. https://doi.org/10.1038/srep39113

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