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arXiv · 2002.09522

Resonant Quantum Search with Monitor Qubits

Frank Wilczek·Hong-Ye Hu·Biao Wu
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Abstract

We present an algorithm for the generalized search problem (searching $k$ marked items among $N$ items) based on a continuous Hamiltonian and exploiting resonance. This resonant algorithm has the same time complexity $O(\sqrt{N/k})$ as the Grover algorithm. A natural extension of the algorithm, incorporating auxiliary "monitor" qubits, can determine $k$ precisely, if it is unknown. The time complexity of our counting algorithm is $O(\sqrt{N})$, similar to the best quantum approximate counting algorithm, or better, given appropriate physical resources.

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Frank Wilczek, Hong-Ye Hu, Biao Wu. 2020-02-21. Resonant Quantum Search with Monitor Qubits. https://doi.org/10.1088/0256-307x%2F37%2F5%2F050304

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