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Fetching marked items from an unsorted database in NMR ensemble computing

L. Xiao·G. L. Long
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Abstract

Searching a marked item or several marked items from an unsorted database is a very difficult mathematical problem. Using classical computer, it requires $O(N=2^n)$ steps to find the target. Using a quantum computer, Grover's algorithm uses $O(\sqrt{N=2^n})$ steps. In NMR ensemble computing, Brushweiler's algorithm uses $\log N$ steps. In this Letter, we propose an algorithm that fetches marked items in an unsorted database directly. It requires only a single query. It can find a single marked item or multiple number of items.

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L. Xiao, G. L. Long. 2001-12-26. Fetching marked items from an unsorted database in NMR ensemble computing. https://doi.org/10.1103/physreva.66.052320

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