Rigorous quantum state tomography for distributed quantum computing

Quantum Physics [Submitted on 10 Apr 2026] Rigorous quantum state tomography for distributed quantum computing Hans Mättig-Vásquez, Aldo Delgado, Luciano Pereira Distributed quantum computing offers a promising approach to scaling quantum devices by networking multiple quantum processors. We present a quantum state tomography protocol tailored for distributed quantum computers that avoids assuming remote entanglement as a primitive resource. The protocol extends projected least-squares (PLS) tomography based on projective 2-designs to systems composed of multiple quantum processors, using only local operations within each processor and classical communication between nodes. Assuming entanglement within each individual quantum processor is trusted, the protocol can be executed using mutually unbiased bases. We derive rigorous, non-asymptotic trace-norm error bounds for the PLS estimator, with explicit exponential dependence on the number of nodes. In addition, we establish certified error bounds for estimating entanglement negativity from the PLS estimator. Numerical simulations for systems of up to seven qubits distributed across several devices validate the theoretical error bounds. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2604.09775 [quant-ph]   (or arXiv:2604.09775v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2604.09775 Focus to learn more Submission history From: Luciano Iván Pereira Valenzuela [view email] [v1] Fri, 10 Apr 2026 18:02:02 UTC (238 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-04 References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)