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arXiv:quant-ph/9808056 · Physical Review Letters

Approximate Quantum Counting on an NMR Ensemble Quantum Computer

Jonathan A. Jones, Michele Mosca

Published Aug 2, 1999• 65 citations
arXivHTMLPDF

Abstract

We demonstrate the implementation of a quantum algorithm for estimating the number of matching items in a search operation using a two qubit nuclear magnetic resonance (NMR) quantum computer.
DOI
10.1103/physrevlett.83.1050

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With a three-bit nuclear magnetic resonance quantum computer, we have experimentally realized a quantum search algorithm that can take a desired function value (or target) t as its input and give the corresponding function argument x0{x}_{0}x0​ such that f(x0)=t{f(x}_{0})=tf(x0​)=t as a result. The function value is not retrieved from an existing table, but evaluated by the search algorithm in the manner of a typical algorithmic search. A single-query version of the quantum search algorithm is used to search for one of two function arguments.
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