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arXiv · 0706.3038

Separability of a family of one parameter W and GHZ multiqubit states using Abe-Rajagopal q-conditional entropy approach

R. Prabhu·A. R. Usha Devi·G. Padmanabha
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Abstract

We employ conditional Tsallis q entropies to study the separability of symmetric one parameter W and GHZ multiqubit mixed states. The strongest limitation on separability is realized in the limit q-->infinity, and is found to be much superior to the condition obtained using the von Neumann conditional entropy (q=1 case). Except for the example of two qubit and three qubit symmetric states of GHZ family, the $q$-conditional entropy method leads to sufficient - but not necessary - conditions on separability.

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R. Prabhu, A. R. Usha Devi, G. Padmanabha. 2007-09-11. Separability of a family of one parameter W and GHZ multiqubit states using Abe-Rajagopal q-conditional entropy approach. https://doi.org/10.1103/physreva.76.042337

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