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Physical Review A

Geometric measure for entanglement in N -qudit pure states

Ali Saif M. Hassan, Pramod S. Joag

Published Oct 1, 2009• 34 citations
Publisher

Abstract

We present a multipartite entanglement measure for $N$-qudit pure states, using the norm of the correlation tensor which occurs in the Bloch representation of the state. We compute this measure for an important class of $N$-qutrit pure states, namely, general GHZ states. We prove that this measure possesses all the essential and many desirable properties expected of a good entanglement measure, including monotonicity. We also discuss the feasibility of the experimental evaluation of this measure for an $N$-qutrit system.

DOI
10.1103/physreva.80.042302

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