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arXiv · 1404.4912

The relation between tangle and local unitary invariants for pure three and four-qubit states

Xin-wei Zha·Yun-Guang Zhang·Jian-Xia Qi·Hai-Yang Song
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Abstract

A new form of local unitary (LU) transformation invariant is given for multi-qubit states . The general relation between tangle and the LU transformation invariant of pure three and four-qubit states is given. We find that the tangle actually is a special LU transformation invariant. Furthermore, the tangle is a important local unitary (LU) transformation invariant which is a nessesary condition for maximally multi-qubit entangled state.

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Xin-wei Zha, Yun-Guang Zhang, Jian-Xia Qi, Hai-Yang Song. 2014-04-19. The relation between tangle and local unitary invariants for pure three and four-qubit states. https://arxiv.org/abs/1404.4912

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