AI 中文总结
该研究采用Quantum Machines的OPX FPGA实现硅双量子点多参数梯度下降反馈稳定化，提升反馈带宽以抑制低频1/f噪声，可维持器件长期稳定性并助力大规模量子点阵列实时控制。
AI 中文摘要
半导体自旋量子比特的长期运行需要主动稳定量子点势以抑制低频电荷噪声。此前研究利用输运电流测量，在硅双量子点上实现了梯度下降反馈（GDFB）方法。我们将该GDFB方法扩展至配备高带宽射频反射测量读出的硅双量子点器件，采用Quantum Machines公司的OPX现场可编程门阵列进行数字信号处理。OPX支持连续多参数梯度计算与快速栅极电压更新，相比此前工作显著提升了有效反馈带宽。该高速稳定方案每个反馈周期含8个步骤，积分时间为25.6μs，可实现5kHz带宽内-6dB的噪声抑制，有效抑制低频1/f噪声，维持器件长时间稳定性，有望为大规模量子点阵列的实时控制提供支持。
英文摘要
Long term operation of semiconductor spin qubits requires active stabilization of quantum dot potentials against low-frequency charge noise. Previous work demonstrated a gradient-descent feedback (GDFB) approach on a silicon double quantum dot utilizing transport current measurements. We extend such a GDFB approach in a silicon double quantum dot device with high-bandwidth rf-reflectometry readout by utilizing a field-programmable gate array, the OPX by Quantum Machines, for digital signal processing. The OPX enables continuous multi-parameter gradient calculation and quick gate voltage updates, significantly increasing the effective feedback bandwidth compared to previous work. By operating with 8 steps per feedback cycle and an integration time of 25.6 $μ$s, this high speed stabilization scheme achieves a -6 dB noise suppression up to a bandwidth of 5 kHz. This effectively suppresses low frequency 1/f noise, maintaining device stability over longer time periods, and potentially enables real-time control in large-scale quantum dot arrays.
Comments4 pages, 5 figures
