Accuracy threshold for concatenated error detection in one dimension

Understand

Estimates of the quantum accuracy threshold often tacitly assume that it is possible to interact arbitrary pairs of qubits in a quantum computer with a failure rate that is independent of the distance between them.

• None of the many physical systems that are candidates for quantum computing possess this property.
• Here we study the performance of a concatenated error-detection code in a system that permits only nearest-neighbor interactions in one dimension.
• We make use of a new message-passing scheme that maximizes the number of errors that can be reliably corrected by the code.