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Ability of entanglement and purity to help to detect systematic experimental errors

Julia Freund1,2, Francesco Basso Basset3,4, Tobias M. Krieger2, Alessandro Laneve3, Mattia Beccaceci3, Michele B. Rota3, Quirin Buchinger5, Saimon F. Covre da Silva2,6, Sandra Stroj7 et al.

Sven Höfling5, Tobias Huber-Loyola5,8, Richard Kueng9, Armando Rastelli2, Rinaldo Trotta3, and Otfried Gühne10

  • 1Institut für Theoretische Physik, Universität Innsbruck, Technikerstraße 21a, 6020 Innsbruck, Austria
  • 2Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, 4040 Linz, Austria
  • 3Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
  • 4Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
  • 5Technical Physics, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
  • 6Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas (UNICAMP), 13083-859 Campinas, Brazil
  • 7Forschungszentrum Mikrotechnik, FH Vorarlberg, Hochschulstraße 1, 6850 Dornbirn, Austria
  • 8Institute of Photonics and Quantum Electronics & IQST, Karlsruhe Institute of Technology, Engesserstr. 5, 76131 Karlsruhe, Germany
  • 9Institute for Integrated Circuits, Johannes Kepler University, Altenberger Straße 69, 4040 Linz, Austria
  • 10Naturwissenschaftlich-Technische Fakultät, Universität Siegen, Walter-Flex-Str. 3, 57068 Siegen, Germany

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Phys. Rev. A 113, 022422 – Published 17 February, 2026

DOI: https://doi.org/10.1103/b74j-xxv2

Abstract

Measurements are central in all quantitative sciences, and a fundamental challenge is to make observations without systematic measurement errors. This holds in particular for quantum information processing, where other error sources, such as noise and decoherence, are unavoidable. Consequently, methods for detecting systematic errors have been developed, but the required quantum state properties are yet unexplored. We theoretically develop a direct and efficient method to detect systematic errors in quantum experiments and demonstrate it experimentally using quantum state tomography of photon pairs emitted from a semiconductor quantum dot. Our method can be scaled to multiqubit systems, and we find that entanglement and quantum states with high purity can help identify systematic errors.

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Phys. Rev. A 113, 022422– Published 17 February, 2026
  • Received 19 March 2025
  • Revised 14 October 2025
  • Accepted 23 December 2025
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