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arXiv · 2106.11124

Designs for a two-dimensional Si quantum dot array with spin qubit addressability

Masahiro Tadokoro·Takashi Nakajima·Takashi Kobayashi·Kenta Takeda·Akito Noiri·Kaito Tomari·Jun Yoneda·Seigo Tarucha·Tetsuo Kodera
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Abstract

Electron spins in Si are an attractive platform for quantum computation, backed with their scalability and fast, high-fidelity quantum logic gates. Despite the importance of two-dimensional integration with efficient connectivity between qubits for medium- to large-scale quantum computation, however, a practical device design that guarantees qubit addressability is yet to be seen. Here, we propose a practical 3 x 3 quantum dot device design and a larger-scale design as a longer-term target. The design goal is to realize qubit connectivity to the four nearest neighbors while ensuring addressability. We show that a 3 x 3 quantum dot array can execute four-qubit Grover's algorithm more efficiently than the one-dimensional counterpart. To scale up the two-dimensional array beyond 3 x 3, we propose a novel structure with ferromagnetic gate electrodes. Our results showcase the possibility of medium-sized quantum processors in Si with fast quantum logic gates and long coherence times.

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Masahiro Tadokoro, Takashi Nakajima, Takashi Kobayashi, Kenta Takeda, Akito Noiri, Kaito Tomari, Jun Yoneda, Seigo Tarucha, Tetsuo Kodera. 2021-06-21. Designs for a two-dimensional Si quantum dot array with spin qubit addressability. https://arxiv.org/abs/2106.11124

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