Demonstration of a quantum error detection code using a square lattice of four superconducting qubits
Abstract
The ability to detect and deal with errors when manipulating quantum systems is a fundamental requirement for faulttolerant quantum computing. Unlike classical bits that are subject to only digital bitflip errors, quantum bits are susceptible to a much larger spectrum of errors, for which any complete quantum errorcorrecting code must account. Whilst classical bitflip detection can be realized via a linear array of qubits, a general faulttolerant quantum errorcorrecting code requires extending into a higherdimensional lattice. Here we present a quantum error detection protocol on a twobytwo planar lattice of superconducting qubits. The protocol detects an arbitrary quantum error on an encoded twoqubit entangled state via quantum nondemolition parity measurements on another pair of error syndrome qubits. This result represents a building block towards larger lattices amenable to faulttolerant quantum error correction architectures such as the surface code.
 Publication:

Nature Communications
 Pub Date:
 April 2015
 DOI:
 10.1038/ncomms7979
 arXiv:
 arXiv:1410.6419
 Bibcode:
 2015NatCo...6.6979C
 Keywords:

 Quantum Physics
 EPrint:
 12 pages, 9 figures