White Noise in Quantum Random Walk Search Algorithm

作     者：马雷 杜江峰 李筠 李卉 KWEK L.C. OH C.H. 

作者机构：Department of Physics Faculty of Science National University of Singapore 10 Lower Kent Ridge Singapore 119260 Department of Physics East China Normal University Shanghai 200062 Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics University of Science and Technology of China Hefei 230026 National Institute of Education Nanyang Technological University 1 Nanyang Walk Singapore 639798 

出 版 物：《Chinese Physics Letters》 (中国物理快报（英文版）)

年 卷 期：2006年第23卷第4期

页      面：779-782页

核心收录：

学科分类：07[理学] 070201[理学-理论物理] 0702[理学-物理学] 

基　　金：the NUS Research Fund of Republic of Singapore 国家973计划 

主　　题：White Noise Walk Search Algorithm 

摘      要：The quantum random walk is a possible approach to construct new quantum search algorithms. It has been shown by Shenvi et al. [Phys. Rev. A 67（2003）52307] that a kind of algorithm can perform an oracle search on a database of N items with O（√N） calling to the oracle, yielding a speedup similar to other quantum search algorithms. We study the effect of white or Gaussian noise on this algorithm. The algorithm loses efficiency when noise is added. We also show that noise on the target state plays a more important role than that on other states. Finally we compare the effects of similar types of noise in the quantum random walk search algorithm and Grover＇s search algorithm.