Title
Quantum algorithm and experimental demonstration for the subset sum problem
Abstract
To solve the subset sum problem, a well-known nondeterministic polynomial-time complete problem that is widely used in encryption and resource scheduling, we propose a feasible quantum algorithm that utilizes fewer qubits to encode and achieves quadratic speedup. Specifically, this algorithm combines an amplitude amplification algorithm with quantum phase estimation, and requires n + t + 1 qubits and O(2((0.5+o(1))n)) operations to obtain the solution, where n is the number of elements, and t is the number of qubits used to store the eigenvalues. To verify the performance of the algorithm, we simulate the algorithm with the online quantum simulator of IBM named ibmq_simulator using Qiskit and then run it on two IBM quantum computers called ibmq_santiago and ibmq_bogota. The experimental results indicate that compared with the brute force algorithm, the proposed algorithm results in quadratic acceleration for the problem of a set S with four elements and two subsets whose sum equals target w. Using the iterator twice, we obtain success probabilities of 0.940 +/- 0.004, 0.751 +/- 0.040, and 0.665 +/- 0.060 on the simulator, ibmq_santiago, and ibmq_bogota, respectively, and the fidelity between the theoretical and experimental quantum states is calculated to be 0.944 +/- 0.002, 0.753 +/- 0.017, and 0.657 +/- 0.028, respectively. If the error rates of the experimental quantum logic gates can be reduced, the success probabilities of the proposed algorithm on real quantum devices can be further improved.
Year
DOI
Venue
2022
10.1007/s11432-021-3334-1
SCIENCE CHINA-INFORMATION SCIENCES
Keywords
DocType
Volume
quantum algorithm, subset sum, quadratic speedup, encryption, algorithm complexity
Journal
65
Issue
ISSN
Citations 
8
1674-733X
0
PageRank 
References 
Authors
0.34
0
11
Name
Order
Citations
PageRank
Qilin Zheng100.34
Pingyu Zhu200.34
Shichuan Xue300.34
Yang Wang439461.44
Chao Wu515018.81
Xinyao Yu6131.45
Miaomiao Yu700.68
Yingwen Liu800.68
Mingtang Deng900.34
Junjie Wu1055147.60
Ping Xu1100.34