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arXiv · 1010.0326

How to decompose arbitrary continuous-variable quantum operations

Seckin Sefi·Peter van Loock
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Abstract

We present a general, systematic, and efficient method for decomposing any given exponential operator of bosonic mode operators, describing an arbitrary multi-mode Hamiltonian evolution, into a set of universal unitary gates. Although our approach is mainly oriented towards continuous-variable quantum computation, it may be used more generally whenever quantum states are to be transformed deterministically, e.g. in quantum control, discrete-variable quantum computation, or Hamiltonian simulation. We illustrate our scheme by presenting decompositions for various nonlinear Hamiltonians including quartic Kerr interactions. Finally, we conclude with two potential experiments utilizing offline-prepared optical cubic states and homodyne detections, in which quantum information is processed optically or in an atomic memory using quadratic light-atom interactions.

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Seckin Sefi, Peter van Loock. 2011-10-18. How to decompose arbitrary continuous-variable quantum operations. https://doi.org/10.1103/physrevlett.107.170501

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