High-fidelity gates with mid-circuit erasure conversion in a metastable neutral atom qubit*

Rydberg atoms in optical tweezer arrays have progressed rapidly in recent years, demonstrating programmable processors and quantum simulators with scaling to hundreds of atoms. Alkaline earth atoms, in particular, provide novel avenues for enhancing coherence, control and scalability. For example, in the context of eventual application in fault-tolerant quantum computing, it is advantages to implement qubits with structured error models, such as detectable erasure errors. In a recent work [1], we demonstrate high-fidelity gates and erasure conversion using a new neutral atom qubit — nuclear spin levels of a long-lived metastable state in 171Yb. The long coherence time and fast excitation to the Rydberg state enable one- and two-qubit gates with fidelities of 0.9990(1) and 0.980(1), respectively. Importantly, we show that 56% of single-qubit gate errors and 33% of two-qubit gate errors are converted into erasure through fast mid-circuit detection of ground state atoms.

[1] S. Ma, G. Liu, P. Peng, et al. Nature 622 279 (2023).