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arXiv · 0808.2989

Multiparty quantum states stabilized by the diagonal subgroup of the local unitary group

David W. Lyons·Scott N. Walck
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Abstract

We classify, up to local unitary equivalence, the set of $n$-qubit states that is stabilized by the diagonal subgroup of the local unitary group. We exhibit a basis for this set, parameterized by diagrams of nonintersecting chords connecting pairs of points on a circle, and give a criterion for when the stabilizer is precisely the diagonal subgroup and not larger. This investigation is part of a larger program to partially classify entanglement type (local unitary equivalence class) via analysis of stabilizer structure.

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David W. Lyons, Scott N. Walck. 2008-10-16. Multiparty quantum states stabilized by the diagonal subgroup of the local unitary group. https://doi.org/10.1103/physreva.78.042314

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