Communications in Theoretical Physics

Comparative Study of Entanglement and Wigner Function for Multi-Qubit GHZ-Squeezed State

Fatima-Zahra Siyouri

Published Dec 1, 2017• 10 citations

Abstract

Abstract In this paper we address the possibility of using the Wigner function to capture the quantum entanglement present in a multi-qubit system. For that purpose, we calculate both the degree of entanglement and the Wigner function for mixed tripartite squeezed states of Greenberger–Horne–Zeilinger (GHZ) type then we compare their behaviors. We show that the role of Wigner function in detecting and quantifying bipartite quantum correlation [Int. J. Mod. Phys. B 30 (2016) 1650187] may be generalized to the multipartite case.

DOI: 10.1088/0253-6102/68/6/729

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