论文标题
驱动电子自旋量子标准的连贯性，与准静态噪声积极脱钩
Coherence of a driven electron spin qubit actively decoupled from quasi-static noise
论文作者
论文摘要
半导体量子点中电子自旋矩的相干性主要来自低频噪声。在过去的十年中，努力通过材料工程来减轻这种噪音，从而大大增加了旋转时间的空转时间。但是，确定控制保真度的自旋操作中环境噪声的作用尚不清楚。我们展示了一个电子自旋量子，其在驱动进化中的一致性受高频电荷噪声而不是任何半导体装置固有的准静态噪声的限制。我们采用了一种反馈控制技术来积极抑制后者，证明了$ 99.04 \ pm 0.23 \，\％$在Alsenide Quantum Dot中的$ 99.04 \ pm 0.23 \，\％$。我们表明，驱动进化的连贯性受到拉比频率下的纵向噪声的限制，该频谱类似于在同位素纯化的硅Qubit中观察到的$ 1/f $噪声。
The coherence of electron spin qubits in semiconductor quantum dots suffers mostly from low-frequency noise. During the last decade, efforts have been devoted to mitigate such noise by material engineering, leading to substantial enhancement of the spin dephasing time for an idling qubit. However, the role of the environmental noise during spin manipulation, which determines the control fidelity, is less understood. We demonstrate an electron spin qubit whose coherence in the driven evolution is limited by high-frequency charge noise rather than the quasi-static noise inherent to any semiconductor device. We employed a feedback control technique to actively suppress the latter, demonstrating a $π$-flip gate fidelity as high as $99.04\pm 0.23\,\%$ in a gallium arsenide quantum dot. We show that the driven-evolution coherence is limited by the longitudinal noise at the Rabi frequency, whose spectrum resembles the $1/f$ noise observed in isotopically purified silicon qubits.
