To date, individual addressing of ion qubits has relied primarily on local Rabi or transition frequency differences between ions created via electromagnetic field spatial gradients or via ion transport operations. Alternatively, it is possible to synthesize arbitrary local one-qubit gates by leveraging local phase differences in a global driving field. Here we report individual addressing of $^{40}$Ca$^+$ ions in a two-ion crystal using axial potential modulation in a global gate laser field. We characterize the resulting gate performance via one-qubit randomized benchmarking, applying different random sequences to each co-trapped ion. We identify the primary error sources and compare the results with single-ion experiments to better understand our experimental limitations. These experiments form a foundation for the universal control of two ions, confined in the same potential well, with a single gate laser beam.

中文翻译：

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通过全局光场中的陷阱电位调制进行单离子寻址

迄今为止，离子量子位的单独寻址主要依赖于局部 Rabi 或通过电磁场空间梯度或通过离子传输操作产生的离子之间的跃迁频率差异。或者，可以通过利用全局驱动场中的局部相位差来合成任意局部单量子位门。在这里，我们报告了在全局栅极激光场中使用轴向电位调制在双离子晶体中单独寻址 $^{40}$Ca$^+$ 离子。我们通过一个量子位随机基准测试来表征由此产生的门性能，将不同的随机序列应用于每个共同捕获的离子。我们确定主要误差源并将结果与​​单离子实验进行比较，以更好地了解我们的实验局限性。这些实验为两种离子的通用控制奠定了基础，