  A minimal depth quantum circuit implementing 5-qubit quantum error correction
in a manner optimized for a linear nearest neighbor architecture is described.
The canonical decomposition is used to construct fast and simple gates that
incorporate the necessary swap operations. Simulations of the circuit's
performance when subjected to discrete and continuous errors are presented. The
relationship between the error rate of a physical qubit and that of a logical
qubit is investigated with emphasis on determining the concatenated error
correction threshold.
