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Sequential semi-device-independent quantum randomness certification

Carles Roch i Carceller1,*, Hanwool Lee2, Jonatan Bohr Brask3, Kieran Flatt4, and Joonwoo Bae4

  • *Contact author: carles.roch_i_carceller@fysik.lu.se
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Phys. Rev. Research 8, 023186 – Published 19 May, 2026

DOI: https://doi.org/10.1103/vb68-jlr3

Abstract

Quantum measurements under realistic conditions reveal only partial information about a system. Yet, by performing sequential measurements on the same system, additional information can be accessed. We investigate this problem in the context of semi-device-independent randomness certification using sequential maximum-confidence measurements. We develop a general framework and versatile numerical methods to bound the amount of certifiable randomness in such scenarios. We further introduce a technique to compute min-tradeoff functions via semidefinite programming duality, thus making the framework suitable for bounding the certifiable randomness against adaptive attacking strategies through entropy accumulation. Our results establish sufficient criteria showing that maximum-confidence measurements enable the distribution and certification of randomness across a sequential measurement chain in single-party systems.

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Phys. Rev. Research 8, 023186– Published 19 May, 2026
  • Received 29 October 2025
  • Revised 2 February 2026
  • Accepted 25 April 2026
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