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Demonstration of qubit operations below a rigorous fault tolerance threshold with gate set tomography.

ABSTRACT: Quantum information processors promise fast algorithms for problems inaccessible to classical computers. But since qubits are noisy and error-prone, they will depend on fault-tolerant quantum error correction (FTQEC) to compute reliably. Quantum error correction can protect against general noise if-and only if-the error in each physical qubit operation is smaller than a certain threshold. The threshold for general errors is quantified by their diamond norm. Until now, qubits have been assessed primarily by randomized benchmarking, which reports a different error rate that is not sensitive to all errors, and cannot be compared directly to diamond norm thresholds. Here we use gate set tomography to completely characterize operations on a trapped-Yb+-ion qubit and demonstrate with greater than 95% confidence that they satisfy a rigorous threshold for FTQEC (diamond norm ≤6.7 × 10-4).

SUBMITTER: Blume-Kohout R

PROVIDER: S-EPMC5330857 | biostudies-other | 2017 Feb

REPOSITORIES: biostudies-other

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Demonstration of qubit operations below a rigorous fault tolerance threshold with gate set tomography.

Blume-Kohout Robin R Gamble John King JK Nielsen Erik E Rudinger Kenneth K Mizrahi Jonathan J Fortier Kevin K Maunz Peter P

Nature communications 20170215

Quantum information processors promise fast algorithms for problems inaccessible to classical computers. But since qubits are noisy and error-prone, they will depend on fault-tolerant quantum error correction (FTQEC) to compute reliably. Quantum error correction can protect against general noise if-and only if-the error in each physical qubit operation is smaller than a certain threshold. The threshold for general errors is quantified by their diamond norm. Until now, qubits have been assessed p ...[more]

PMID: 28198466

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