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Quantum computation over continuous variables

Seth Lloyd·Samuel L. Braunstein
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Abstract

This paper provides necessary and sufficient conditions for constructing a universal quantum computer over continuous variables. As an example, it is shown how a universal quantum computer for the amplitudes of the electromagnetic field might be constructed using simple linear devices such as beam-splitters and phase shifters, together with squeezers and nonlinear devices such as Kerr-effect fibers and atoms in optical cavities. Such a device could in principle perform `quantum floating point' computations. Problems of noise, finite precision, and error correction are discussed.

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Seth Lloyd, Samuel L. Braunstein. 1998-10-27. Quantum computation over continuous variables. https://doi.org/10.1103/physrevlett.82.1784

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