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Quantum synthesis of arbitrary unitary operators

B. Hladky·G. Drobny·V. Buzek
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Abstract

Nature provides us with a restricted set of microscopic interactions. The question is whether we can synthesize out of these fundamental interactions an arbitrary unitary operator. In this paper we present a constructive algorithm for realization of any unitary operator which acts on a (truncated) Hilbert space of a single bosonic mode. In particular, we consider a physical implementation of unitary transformations acting on 1-dimensional vibrational states of a trapped ion. As an example we present an algorithm which realizes the discrete Fourier transform.

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B. Hladky, G. Drobny, V. Buzek. 1999-05-14. Quantum synthesis of arbitrary unitary operators. https://doi.org/10.1103/physreva.61.022102

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