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arXiv:quant-ph/0604202

Unitary invariants of qubit systems

Frédéric Toumazet, Jean-Gabriel Luque, Jean‐Yves Thibon

Published Apr 27, 2006• 5 citations
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Abstract

We give an algorithm allowing to construct bases of local unitary invariants of pure k-qubit states from the knowledge of polynomial covariants of the group of invertible local filtering operations. The simplest invariants obtained in this way are explicited and compared to various known entanglement measures. Complete sets of generators are obtained for up to four qubits, and the structure of the invariant algebras is discussed in detail.

DOI
10.48550/arxiv.quant-ph/0604202

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