Quantum Information & Computation
Volume 26
RESEARCH ARTICLE Open access

Implementation And Analysis of Regev’s Quantum Factorization Algorithm

Przemysław Pawlitko, Natalia Moćko, Marcin Niemiec, Piotr Chołda

Author affiliations
  • Przemysław Pawlitko1
  • Natalia Moćko1
  • Marcin Niemiec1
  • Piotr Chołda1
  1. AGH University of Krakow, Institute of Telecommunications and Cybersecurity, Mickiewicza 30, Krakow, Poland

pp. 230-252 · 10.2478/qic-2026-0012

Abstract

Quantum computing represents a significant advancement in computational capabilities. Of particular concern is its impact on asymmetric cryptography through, notably, Shor’s algorithm and the more recently developed Regev’s algorithm for factoring composite numbers. We present our implementation of the latter with the aim of exposing experimental phenomena. Our analysis encompasses both quantum simulation results and classical component examples, with particular emphasis on comparative cases between Regev’s and Shor’s algorithms. Our experimental results reveal that Regev’s algorithm outperforms Shor’s algorithm for certain composite numbers in practice. However, we observed significant performance variations across different input values. Despite Regev’s algorithm’s theoretical asymptotic advantage in effectiveness, our implementation exhibited longer execution times than Shor’s algorithm for small-integer factorization in both quantum and classical components. These findings offer insights into the practical challenges and performance characteristics of implementing Regev’s algorithm in realistic quantum computing scenarios.
Open accessCC BY-NC-ND 4.0

Keywords

  • factorization
  • quantum algorithms
  • quantum computers
  • Regev’s algorithm
  • Shor’s algorithm

Suggested citation

Przemysław Pawlitko, Natalia Moćko, Marcin Niemiec, Piotr Chołda (2026). Implementation And Analysis of Regev’s Quantum Factorization Algorithm. Quantum Information & Computation, 26(1), 230-252. https://doi.org/10.2478/qic-2026-0012

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