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arXiv · 2412.13266

All pure multipartite entangled states of qubits can be self-tested up to complex conjugation

Maria Balanzó-Juandó·Andrea Coladangelo·Remigiusz Augusiak·Antonio Acín·Ivan Šupić
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Abstract

Self-testing refers to the certification of quantum states and measurements based entirely on the correlations exhibited by measurements on separate subsystems. In the bipartite case, self-testing of states has been completely characterized, up to local isometries, as there exist protocols that self-test arbitrary pure states of any local dimension. Much less is known in the multipartite case, where an important difference with respect to the bipartite case appears: there exist multipartite states that are not equivalent, up to local isometries, to their complex conjugate. Thus, any self-testing characterization must in general be complete up to not only local unitaries, but also complex conjugation. Under these premises, in this work, we give a complete characterization of self-testing in the multipartite qubit case.

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Maria Balanzó-Juandó, Andrea Coladangelo, Remigiusz Augusiak, Antonio Acín, Ivan Šupić. 2024-12-17. All pure multipartite entangled states of qubits can be self-tested up to complex conjugation. https://arxiv.org/abs/2412.13266

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