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arXiv · 2404.01640

Deterministic Search on Complete Bipartite Graphs by Continuous Time Quantum Walk

Honghong Lin·Yun Shang
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Abstract

This paper presents a deterministic search algorithm on complete bipartite graphs. Our algorithm adopts the simple form of alternating iterations of an oracle and a continuous-time quantum walk operator, which is a generalization of Grover's search algorithm. We address the most general case of multiple marked states, so there is a problem of estimating the number of marked states. To this end, we construct a quantum counting algorithm based on the spectrum structure of the search operator. To implement the continuous-time quantum walk operator, we perform Hamiltonian simulation in the quantum circuit model. We achieve simulation in constant time, that is, the complexity of the quantum circuit does not scale with the evolution time.

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Honghong Lin, Yun Shang. 2024-04-02. Deterministic Search on Complete Bipartite Graphs by Continuous Time Quantum Walk. https://arxiv.org/abs/2404.01640

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