We demonstrate key multi-qubit quantum-logic primitives in a dual-species trapped-ion system based on \({}^{40}\)Ca\({}^{+}\) and \({}^{88}\)Sr\({}^{+}\) ions, using two optical qubits with quantum-logic-control frequencies in the red to near-infrared range. With all ionization, cooling, and control wavelengths in a wavelength band similar for the two species and centered in the visible, and with a favorable mass ratio for sympathetic cooling, this pair is a promising candidate for scalable quantum information processing. Same-species and dual-species two-qubit gates, based on the Mølmer–Sørensen interaction and performed in a cryogenic surface-electrode trap, are characterized via the fidelity of generated entangled states; we achieve fidelities of 98.8(2)% and 97.5(2)% in Ca\({}^{+}\)–Ca\({}^{+}\) and Sr\({}^{+}\)–Sr\({}^{+}\) gates, respectively. For a similar Ca\({}^{+}\)–Sr\({}^{+}\) gate, we achieve a fidelity of 94.3(3)%, and carrying out a Sr\({}^{+}\)–Sr\({}^{+}\) gate performed with a Ca\({}^{+}\) sympathetic cooling ion in a Sr\({}^{+}\)–Ca\({}^{+}\)–Sr\({}^{+}\) crystal configuration, we achieve a fidelity of 95.7(3)%. These primitives form a set of trapped-ion capabilities for logic with sympathetic cooling and ancilla readout or state transfer for general quantum computing and communication applications.

我们基于\（{} ^ {40} \） Ca \ {{} ^ {+} \）和\（{} ^ {88 } \）高级\（{} ^ {+} \）离子，使用两个光学量子位，其量子逻辑控制频率在红色至近红外范围内。由于所有离子化，冷却和控制波长都在两个物种相似且在可见光中居中的波长带中，并且以有利的质量比用于同感冷却，因此这对可伸缩量子信息处理是一个有前途的候选对象。基于Mølmer-Sørensen相互作用并在低温表面电极阱中进行的同种和双种双量子位门的特征在于产生的纠缠态的保真度。我们在Ca \（{} ^ {+} \）– Ca \（{} ^ {+} \）和Sr \（{} ^ {+} \ ） –Sr \（{} ^ {+} \）门。对于类似的钙\（{} ^ {+} \）– Sr \（{} ^ {+} \）门，我们实现了94.3（3）％的保真度，并执行了Sr \（{} ^ {+} \） -Sr \（{} ^ {+} \）栅极与钙进行\（{} ^ {+} \）交感神经冷却离子在一个高级\（{} ^ {+} \） -Ca \（{} ^ {+} \）– Sr \（{} ^ {+} \）晶体配置，我们实现了95.7（3）％的保真度。这些原语形成了一组具有捕获能力的逻辑功能，具有用于一般量子计算和通信应用的同感冷却和辅助读出或状态转移的逻辑。