Single Electron Router in Silicon Quantum Dot Array*

For the realization of large-scale quantum computers based on two-dimensional quantum dot arrays in solid-state devices, technologies for the free transport of electrons on the arrays are essential. In particular, controlling the electron routes in branching paths in two-dimensional quantum dot arrays is necessary. Previously, we developed an electron transport technology using a single-electron pump built on a silicon quantum dot array [1]. Here, we develop a single-electron router [2]. It routes electrons periodically emitted from the single-electron pump to the right or left in a branching path of electrons. We showed that accurate routing operation at 100 MHz can be achieved by applying a sinusoidal signal synchronized with the single-electron pump to the switching gate pair in the branching path and to the assist gate in front of it and adjusting their phases. The behavior of this single-electron router is analyzed by a model based on the Wigner representation in energy-time space. We show this model can fit experimental results and estimate the minimum error. Our silicon single-electron router is valuable not only for quantum computing but also for stable quantum metrology with single-electron pumps and as a component of electron quantum optics experiments.

References

[1] T. Utsugi et al., Jpn. J. Appl. Phys. 62, 1020 (2023)

[2] arXiv:2308.05271