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arXiv · 2501.00409

Supersinglets can be self-tested with perfect quantum strategies

Debashis Saha·Adán Cabello
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Abstract

Supersinglets are states of spin-zero of $d \ge 3$ particles of $d$ levels. They are invariant under unitary transformations of the form $U^{\otimes d}$ and have applications in metrology, error protection, and communication. They also violate some specific Bell inequalities. However, none any of these applications {\em require} supersinglets nor do any of these Bell inequality violations capture the unique properties of the supersinglets. This leads to two questions. Question 1 is whether there exists a task that can be solved only with supersinglets. Question 2 is whether supersinglets can produce a unique $d$-partite, $d$-dimensional nonlocal signature. We answer both questions affirmatively by presenting a protocol that self-test all supersinglets by producing $d$-partite, $d$-dimensional {\em perfect} quantum strategies for any $d \ge 3$.

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Debashis Saha, Adán Cabello. 2024-12-31. Supersinglets can be self-tested with perfect quantum strategies. https://doi.org/10.1103/3ymw-sn2z

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