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arXiv · 2209.02259

Feedback-based active reset of a spin qubit in silicon

Takashi Kobayashi·Takashi Nakajima·Kenta Takeda·Akito Noiri·Jun Yoneda·Seigo Tarucha
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Abstract

Feedback control of qubits is a highly demanded technique for advanced quantum information protocols such as quantum error correction. Here we demonstrate active reset of a silicon spin qubit using feedback control. The active reset is based on quantum non-demolition readout of the qubit and feedback according to the readout results, which is enabled by hardware data processing and sequencing. We incorporate a cumulative readout technique to the active reset protocol, enhancing initialization fidelity above a limitation imposed by accuracy of the single QND measurement fidelity. Based on an analysis of the reset protocol, we suggest a way to achieve the initialization fidelity sufficient for the fault-tolerant quantum computation.

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Takashi Kobayashi, Takashi Nakajima, Kenta Takeda, Akito Noiri, Jun Yoneda, Seigo Tarucha. 2022-09-06. Feedback-based active reset of a spin qubit in silicon. https://doi.org/10.1038/s41534-023-00719-3

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