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Macroscopically distinct quantum superposition states as a bosonic code for amplitude damping

P. T. Cochrane·G. J. Milburn·W. J. Munro
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Abstract

We show how macroscopically distinct quantum superposition states (Schroedinger cat states) may be used as logical qubit encodings for the correction of spontaneous emission errors. Spontaneous emission causes a bit flip error which is easily corrected by a standard error correction circuit. The method works arbitrarily well as the distance between the amplitudes of the superposed coherent states increases.

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P. T. Cochrane, G. J. Milburn, W. J. Munro. 1998-11-23. Macroscopically distinct quantum superposition states as a bosonic code for amplitude damping. https://doi.org/10.1103/physreva.59.2631

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