Entangling gates with error rates reaching the threshold for quantum error correction have been reported for CZ gates using adiabatic longitudinal control based on the interaction between the |11〉 and |20〉 states. Here, we design and implement nonadiabatic CZ gates, which outperform adiabatic gates in terms of speed and fidelity, with gate times reaching \(1.25/(2\sqrt 2 g_{01,10})\), and fidelities reaching 99.54 ± 0.08%. Nonadiabatic gates are found to have proportionally less incoherent error than adiabatic gates thanks to their fast gate times, which leave more room for further improvements in the design of the control pules to eliminate coherent errors. We also show that state leakage can be reduced to below 0.2% with optimisation. Furthermore, the gate optimisation process is highly feasible: experimental optimisation can be expected to take less than four hours. Finally, the gate design process can be extended to CCZ gates, and our preliminary results suggest that this process would be feasible as well, if we can measure the CCZ fidelity separate from the initialisation and readout errors in experimental optimisation.

据报道，基于| 11〉和| 20〉状态之间的相互作用，采用绝热纵向控制的CZ门的纠错率达到量子纠错阈值的纠缠门。在这里，我们设计并实现了非绝热CZ门，其速度和保真度优于绝热门，门时间达到\（1.25 /（2 \ sqrt 2 g_ {01,10}）\），保真度达到99.54±0.08％。非绝热门由于其快速的闸门时间而比绝热门具有成比例地较小的非相干误差，这为控制桩的设计留出更多空间来进一步改善以消除相干误差。我们还表明，通过优化可以将状态泄漏降低到0.2％以下。此外，门优化过程是高度可行的：预计实验优化将花费不到四个小时。最后，闸门设计过程可以扩展到CCZ闸门，我们的初步结果表明，如果我们可以将CCZ保真度与实验优化中的初始化和读出误差分开进行测量，则该过程也是可行的。