2007/01/31 by A. Gábris, A. Gabris, T. Kiss +2 · 2 citations
Computer Science · Physics and Astronomy · #Neural Networks and Reservoir Computing #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #quant-ph
paper · pdf · doi:10.1103/physreva.76.062315
published as Phys. Rev. A 76, 062315 (2007) · 10 pages, 10 figures. Two figures added for clarity, also made improvements to the text
arxiv created 2007/09/27 · openalex publication_date 2007/12/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We analyze the realization of a quantum-walk search algorithm in a passive, linear optical network. The specific model enables us to consider the effect of realistic sources of noise and losses on the search efficiency. Photon loss uniform in all directions is shown to lead to the rescaling of search time. Deviation from directional uniformity leads to the enhancement of the search efficiency compared to uniform loss with the same average. In certain cases even increasing loss in some of the directions can improve search efficiency. We show that while we approach the classical limit of the general search algorithm by introducing random phase fluctuations, its utility for searching is lost. Using numerical methods, we found that for static phase errors the averaged search efficiency displays a damped oscillatory behavior that asymptotically tends to a nonzero value.