AI 中文总结
本研究利用抗退相量子噪声谱，在囚禁离子处理器中识别并表征轴向运动诱导的控制噪声，分离相关噪声与固有控制噪声，实现多量子比特位置相关控制噪声的同步表征，并确定了可抑制噪声的光束拐点工作区域。
AI 中文摘要
量子处理器中的固有噪声过程通常难以分离，因为多种误差机制会导致相同的相干性损失。本研究采用抗退相的量子噪声谱方法，在单独寻址的囚禁离子处理器中识别并表征由轴向运动诱导的控制噪声。当离子运动垂直于寻址光束时，热轴向运动会与光束轮廓耦合，产生有效的振幅控制噪声。研究表明，该噪声主要由局部光束曲率决定，表现为重构控制噪声谱中的低频分量。通过改变离子在光束轮廓内的位置，研究人员将依赖曲率的轴向运动噪声与不依赖曲率的固有控制噪声分离开，并提取出该平台上难以获取的运动参数。此外，该协议还被并行应用于四离子寄存器，证明了一种可同时表征多个量子比特位置相关控制噪声的谱学方法。本研究结果确定了光束拐点为可抑制轴向运动诱导噪声的工作区域，但代价是拉比速率降低，这一发现与PRX Quantum 3, 010334 (2022)中的结论一致。
英文摘要
Native noise processes in quantum processors are often difficult to isolate because multiple error mechanisms contribute to the same measured loss of coherence. Here we use dephasing-robust quantum noise spectroscopy to identify and characterize control noise induced by axial motion in an individually-addressed trapped-ion processor. When the ion motion is transverse to the addressing beam, thermal axial motion couples to the beam profile and produces effective amplitude control noise. We show that this noise is governed primarily by the local beam curvature and appears as a low-frequency contribution to the reconstructed control-noise spectrum. By varying the ion position within the beam profile, we separate curvature-dependent axial-motion noise from curvature-independent native control noise and extract motional parameters that are otherwise difficult to access on this platform. We also apply the protocol in parallel to a four-ion register, demonstrating a spectroscopic method for simultaneous characterization of position-dependent control noise across multiple qubits. The results of this study identify beam inflection points as operating regions that suppress axial-motion-induced noise at the cost of reduced Rabi rate, as found in PRX Quantum 3, 010334 (2022).
Comments15 pages, 8 figures
