Quantum Computation over Continuous Variables

  title={Quantum Computation over Continuous Variables},
  author={S. Lloyd and Samuel L. Braunstein},
  journal={Physical Review Letters},
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 “floating point… 

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