Entanglement generation in trapped-ion systems has relied thus far on two distinct but related geometric phase gate techniques: Mølmer-Sørensen and light-shift gates. We recently proposed a variant of the light-shift scheme where the qubit levels are separated by an optical frequency [B. C. Sawyer and K. R. Brown, Phys. Rev. A 103, 022427 (2021)]. Here we report an experimental demonstration of this entangling gate using a pair of ${{}^{40}\mathrm{Ca}}^{+}$ ions in a cryogenic surface-electrode ion trap and a commercial, high-power, 532 nm Nd:YAG laser. Generating a Bell state in $35\mu \mathrm{s}$, we directly measure an infidelity of $6(3)\times {10}^{-4}$ without subtraction of experimental errors. The 532 nm gate laser wavelength suppresses intrinsic photon scattering error to $\sim 1\times {10}^{-5}$.

中文翻译：

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使用 Ca+40 光学量子位的高保真钟态制备

迄今为止，俘获离子系统中的纠缠生成依赖于两种不同但相关的几何相位门技术：Mølmer-Sørensen 和光移门。我们最近提出了一种光移方案的变体，其中量子位水平由光频率分隔 [B. C. Sawyer 和 K. R. Brown，物理学。修订版 A 103 , 022427 (2021)]。在这里，我们报告了使用一对纠缠门的实验演示${{}^{40}钙}^{+}$低温表面电极离子阱和商用高功率 532 nm Nd:YAG 激光器中的离子。生成 Bell 状态$35\mu \mathrm{秒}$，我们直接测量 $6(3)\times {10}^{-4}$不减去实验误差。532 nm 栅极激光波长可将固有光子散射误差抑制到$～1\times {10}^{-5}$.