arXiv:1105.3086 · Journal of Physics A Mathematical and Theoretical

All degree 6 local unitary invariants of k qudits

Szilárd Szalay

Published Jan 20, 2012• 9 citations

Abstract

We give explicit index-free formulae for all the degree 6 (and also degree 4 and 2) algebraically independent local unitary invariant polynomials for finite-dimensional k -partite pure and mixed quantum states. We carry this out using graph-technical methods, which provide illustrations for this abstract topic.

DOI: 10.1088/1751-8113/45/6/065302

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