Erasure conversion for faulttolerant quantum computing in alkaline earth Rydberg atom arrays
Abstract
Executing quantum algorithms on errorcorrected logical qubits is a critical step for scalable quantum computing, but the requisite numbers of qubits and physical error rates are demanding for current experimental hardware. Recently, the development of error correcting codes tailored to particular physical noise models has helped relax these requirements. In this work, we propose a qubit encoding and gate protocol for ^{171}Yb neutral atom qubits that converts the dominant physical errors into erasures, that is, errors in known locations. The key idea is to encode qubits in a metastable electronic level, such that gate errors predominantly result in transitions to disjoint subspaces whose populations can be continuously monitored via fluorescence. We estimate that 98% of errors can be converted into erasures. We quantify the benefit of this approach via circuitlevel simulations of the surface code, finding a threshold increase from 0.937% to 4.15%. We also observe a larger code distance near the threshold, leading to a faster decrease in the logical error rate for the same number of physical qubits, which is important for nearterm implementations. Erasure conversion should benefit any error correcting code, and may also be applied to design new gates and encodings in other qubit platforms.
 Publication:

Nature Communications
 Pub Date:
 August 2022
 DOI:
 10.1038/s41467022320946
 arXiv:
 arXiv:2201.03540
 Bibcode:
 2022NatCo..13.4657W
 Keywords:

 Quantum Physics;
 Physics  Atomic Physics
 EPrint:
 Nature Communications 13, 4657 (2022)