Solid state qubits realized in superconducting circuits are potentially scalable. However, strong decoherence may be transferred to the qubits by various elements of the circuits that couple individual qubits, particularly when coupling is implemented over long distances. We propose here an encoding that provides full protection against errors originating from these coupling elements, for a chain of superconducting qubits with a nearest neighbor anisotropic $XY$-interaction. The encoding is also seen to provide partial protection against errors deriving from general electronic noise.

• Received 18 April 2005

DOI:https://doi.org/10.1103/PhysRevB.72.064511