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State preparation based on Grover's algorithm in the presence of global information about the state

Andrei N. Soklakov·Ruediger Schack
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Abstract

In a previous paper [quant-ph/0408045] we described a quantum algorithm to prepare an arbitrary state of a quantum register with arbitrary fidelity. Here we present an alternative algorithm which uses a small number of quantum oracles encoding the most significant bits of the absolute value of the complex amplitudes, and a small number of oracles encoding the most significant bits of the phases. The algorithm given here is considerably simpler than the one described in [quant-ph/0408045], on the assumption that a sufficient amount of knowledge about the distribution of the absolute values of the complex amplitudes is available.

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Andrei N. Soklakov, Ruediger Schack. 2004-11-01. State preparation based on Grover's algorithm in the presence of global information about the state. https://doi.org/10.1134/1.2034606

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