Fault tolerance with bare ancillary qubits for a [[7,1,3]] code

Journal Article (Journal Article)

We present a [[7,1,3]] quantum error-correcting code that is able to achieve fault-tolerant syndrome measurement using one ancillary qubit per stabilizer for an error model of independent single-qubit Pauli errors. All single-qubit Pauli errors on the ancillary qubits propagate to form exclusively correctable errors on the data qubits. The situation changes for error models with two-qubit Pauli errors. We compare the level-1 logical error rates under two noise models: the standard Pauli symmetric depolarizing error model and an anisotropic error model. The anisotropic model is motivated by control errors on two-qubit gates commonly applied to trapped ion qubits. We find that one ancillary qubit per syndrome measurement is sufficient for fault-tolerance for the anisotropic error, but is not sufficient for the standard depolarizing errors. We then show how to achieve fault tolerance for the standard depolarizing errors by adding flag qubits to check for errors on select ancillary qubits. Our results on this [[7,1,3]] code demonstrates how physically motivated noise models may simplify fault-tolerant protocols.

Full Text

Duke Authors

Cited Authors

  • Li, M; Gutiérrez, M; David, SE; Hernandez, A; Brown, KR

Published Date

  • September 28, 2017

Published In

Volume / Issue

  • 96 / 3

Electronic International Standard Serial Number (EISSN)

  • 2469-9934

International Standard Serial Number (ISSN)

  • 2469-9926

Digital Object Identifier (DOI)

  • 10.1103/PhysRevA.96.032341

Citation Source

  • Scopus