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Register a new userProtecting Quantum Information Encoded in Decoherence Free States Against Exchange Errors
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Added by
Dr. Daniel A. Lidar
Publication date
1999
fields
Physics
and research's language is
English
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The exchange interaction between identical qubits in a quantum information processor gives rise to unitary two-qubit errors. It is shown here that decoherence free subspaces (DFSs) for collective decoherence undergo Pauli errors under exchange, which however do not take the decoherence free states outside of the DFS. In order to protect DFSs against these errors it is sufficient to employ a recently proposed concatenated DFS-quantum error correcting code scheme [D.A. Lidar, D. Bacon and K.B. Whaley, Phys. Rev. Lett. {bf 82}, 4556 (1999)].
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