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arXiv · 2003.02285

Device-Independent Certification of Genuinely Entangled Subspaces

Flavio Baccari·Remigiusz Augusiak·Ivan Šupić·Antonio Acín
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Abstract

Self-testing is a procedure for characterizing quantum resources with the minimal level of trust. Up to now it has been used as a device-independent certification tool for particular quantum measurements, channels, and pure entangled states. In this work we introduce the concept of self-testing more general entanglement structures. More precisely, we present the first self-tests of an entangled subspace - the five-qubit code and the toric code. We show that all quantum states maximally violating a suitably chosen Bell inequality must belong to the corresponding code subspace, which remarkably includes also mixed states.

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Flavio Baccari, Remigiusz Augusiak, Ivan Šupić, Antonio Acín. 2020-03-04. Device-Independent Certification of Genuinely Entangled Subspaces. https://doi.org/10.1103/physrevlett.125.260507

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