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arXiv · 1912.06959

Efficient quantum algorithm for solving structured problems via multi-step quantum computation

Hefeng Wang·Sixia Yu·Hua Xiang
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Abstract

In classical computation, a problem can be solved in multiple steps where calculated results of each step can be copied and used repeatedly. While in quantum computation, it is difficult to realize a similar multi-step computation process because the no-cloning theorem forbids making copies of an unknown quantum state perfectly. We find a method based on quantum resonant transition to protect and reuse an unknown quantum state that encodes calculated results of an intermediate step without making copies of the state, and present a quantum algorithm that solves a problem via a multi-step quantum computation process. This algorithm can achieve an exponential speedup over classical algorithms in solving a type of structured search problems.

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Hefeng Wang, Sixia Yu, Hua Xiang. 2019-12-15. Efficient quantum algorithm for solving structured problems via multi-step quantum computation. https://doi.org/10.1103/physrevresearch.5.l012004

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