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Poincare series for local unitary invariants of mixed states of the qubit-qutrit system

Dragomir Z. Djokovic
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Abstract

We consider the mixed states of the bipartite quantum system with the first party a qubit and the second a qutrit. The group of local unitary transformations of the system, ignoring the overall phase factor, is the direct product G of SU(2) and SU(3). We compute the simply graded Poincare series of the algebra of G-invariant polynomial functions on the set of mixed states of the system, and construct several low degree invariants.

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Dragomir Z. Djokovic. 2006-05-01. Poincare series for local unitary invariants of mixed states of the qubit-qutrit system. https://arxiv.org/abs/quant-ph/0605018

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