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Constructing finite dimensional codes with optical continuous variables

S. Pirandola·S. Mancini·D. Vitali·P. Tombesi
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Abstract

We show how a qubit can be fault-tolerantly encoded in the infinite-dimensional Hilbert space of an optical mode. The scheme is efficient and realizable with present technologies. In fact, it involves two travelling optical modes coupled by a cross-Kerr interaction, initially prepared in coherent states, one of which is much more intense than the other. At the exit of the Kerr medium, the weak mode is subject to a homodyne measurement and a quantum codeword is conditionally generated in the quantum fluctuations of the intense mode.

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S. Pirandola, S. Mancini, D. Vitali, P. Tombesi. 2004-02-26. Constructing finite dimensional codes with optical continuous variables. https://doi.org/10.1209/epl%2Fi2004-10203-9

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