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Multi-object searching algorithm using subgrouped oracles

Jin-Yuan Hsieh·Che-Ming Li·Der-San Chuu
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Abstract

We present in this work, if a set of well organized suboracles is available, an algorithm for multiobject search with certainty in an unsorted database of $N$ items. Depending on the number of the objects, the technique of phase tunning is included in the algorithm. If one single object is to be searched, this algorithm performs a factor of two improvement over the best algorithm for a classical sorted database. While if the number of the objects is larger than one, the algorithm requires slightly less than $\log_{4}N$ queries, but no classical counterpart exists since the resulting state is a superposition of the marked states.

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Jin-Yuan Hsieh, Che-Ming Li, Der-San Chuu. 2002-06-16. Multi-object searching algorithm using subgrouped oracles. https://arxiv.org/abs/quant-ph/0205175

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