Distributed exact Grover’s algorithm  

作　　者：Xu Zhou Daowen Qiu Le Luo 

机构地区：[1]Institute of Quantum Computing and Computer Theory,School of Computer Science and Engineering,Sun Yat-sen University,Guangzhou 510006,China [2]The Guangdong Key Laboratory of Information Security Technology,Sun Yat-sen University,Guangzhou 510006,China [3]School of Physics and Astronomy,Sun Yat-sen University,Zhuhai 519082,China [4]QUDOOR Co,Ltd.,Beijing 100089,China

出　　处：《Frontiers of physics》2023年第5期255-279,共25页物理学前沿（英文版）

基　　金：supported in part by the National Natural Science Foundation of China(Nos.61572532 and 61876195);the Natural Science Foundation of Guangdong Province of China(No.2017B030311011).

摘　　要：Distributed quantum computation has gained extensive attention.In this paper,we consider a search problem that includes only one target item in the unordered database.After that,we propose a distributed exact Grover’s algorithm(DEGA),which decomposes the original search problem into■n/2■parts.Specifically,(i)our algorithm is as exact as the modified version of Grover’s algorithm by Long,which means the theoretical probability of finding the objective state is 100%;(ii)the actual depth of our circuit is 8(n mod 2)+9,which is less than the circuit depths of the original and modified Grover’s algorithms,1+8■π/4√2^(n)■and 9+8■π/4√2^(n)-1/2■,respectively.It only depends on the parity of n,and it is not deepened as n increases;(iii)we provide particular situations of the DEGA on MindQuantum(a quantum software)to demonstrate the practicality and validity of our method.Since our circuit is shallower,it will be more resistant to the depolarization channel noise.

关 键 词：distributed quantum computation search problem distributed exact Grover’s algorithm(DEGA) MindQuantum the depolarization channel noise 

分 类 号：O413[理学—理论物理]