Towards a fault-tolerant universal set of microwave driven quantum gates with trapped ions

Quantum computing will eventually require a complete set of quantum gates, with a sufficiently low gate-errors-rate to allow fault tolerance [1]. We implement single- and two-qubit gates using microwave-gradients [2] as a scalable alternative to the more widely spread optical addressing techniques, which are typically limited by photon scattering. The oscillating gradients are generated by embedded conductors inside the trap structure. We obtain a preliminary infidelity of <10−3 for single-qubit gates and approaching 10−3 for two-qubit operations using this fully integrated approach. The two-qubit gates are shown to be robust with respect to motional quantum bus noise, due to a tailored amplitude modulation protocol [3].