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arXiv · quant-ph/0112054

Combined encoding and decoupling solution to problems of decoherence and design in solid-state quantum computing

Mark S. Byrd·Daniel A. Lidar
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Abstract

Proposals for scalable quantum computing devices suffer not only from decoherence due to the interaction with their environment, but also from severe engineering constraints. Here we introduce a practical solution to these major concerns, addressing solid state proposals in particular. Decoherence is first reduced by encoding a logical qubit into two qubits, then completely eliminated by an efficient set of decoupling pulse sequences. The same encoding removes the need for single-qubit operations, that pose a difficult design constraint. We further show how the dominant decoherence processes can be identified empirically, in order to optimize the decoupling pulses.

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Mark S. Byrd, Daniel A. Lidar. 2002-06-18. Combined encoding and decoupling solution to problems of decoherence and design in solid-state quantum computing. https://doi.org/10.1103/physrevlett.89.047901

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