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  • Open Access

Optimization of experimental quantum randomness expansion

Amelie Piveteau1, Alban Seguinard1, Piotr Mironowicz2,1,3,*, and Mohamed Bourennane1

  • *Contact author: piotr.mironowicz@gmail.com
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Phys. Rev. Applied 24, 044096 – Published 30 October, 2025

DOI: https://doi.org/10.1103/hc3f-3pbw

Abstract

Quantum technologies provide many applications for information processing tasks that are impossible to realize within classical physics. These capabilities include such fundamental resources as generating secure, i.e., private and unpredictable random values. Yet, the problem of quantifying the amount of generated randomness is still not fully solved. This work presents a comprehensive analysis of the design and performance optimization of a quantum random number generator (QRNG) based on Bell inequality violations. We investigate key protocol parameters, including the smoothing parameter (ϵs), test round probability (γ), and switching delays, and their effects on the generation rate and quality of randomness. We identify optimal ranges for γ and pΩ (the protocol’s nonaborting probability) to balance the trade-off between randomness consumption and net randomness generation. We investigate the impact of the laser power on the overall generation rate. We explore the impact of switching delays on the system’s performance, providing strategies to mitigate these effects. The work provides practical guidelines for the efficient and secure design of QRNG systems and other cryptographic protocols.

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Phys. Rev. Applied 24, 044096– Published 30 October, 2025
  • Received 7 November 2024
  • Revised 28 July 2025
  • Accepted 12 August 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by Bibsam.

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