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arXiv · 1409.0088

Quantum digital-to-analog conversion algorithm using decoherence

Akira SaiToh
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Abstract

We consider the problem of mapping digital data encoded on a quantum register to analog amplitudes in parallel. It is shown to be unlikely that a fully unitary polynomial-time quantum algorithm exists for this problem; NP becomes a subset of BQP if it exists. In the practical point of view, we propose a nonunitary linear-time algorithm using quantum decoherence. It tacitly uses an exponentially large physical resource, which is typically a huge number of identical molecules. Quantumness of correlation appearing in the process of the algorithm is also discussed.

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Akira SaiToh. 2014-08-30. Quantum digital-to-analog conversion algorithm using decoherence. https://arxiv.org/abs/1409.0088

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