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Unitary Gate Synthesis for Continuous Variable Systems

Jaromir Fiurasek
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Abstract

We investigate the synthesis of continuous-variable two-mode unitary gates in the setting where two modes A and B are coupled by a fixed quadratic Hamiltonian H. The gate synthesis consists of a sequence of evolutions governed by Hamiltonian H interspaced by local phase shifts applied to A and B. We concentrate on protocols that require the minimum necessary number of steps and we show how to implement the beam splitter and the two-mode squeezer in just three steps. Particular attention is paid to the Hamiltonian x_A p_B that describes the effective off-resonant interaction of light with the collective atomic spin.

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Jaromir Fiurasek. 2003-03-13. Unitary Gate Synthesis for Continuous Variable Systems. https://doi.org/10.1103/physreva.68.022304

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