Fig. 9
From: A geometric formulation to measure global and genuine entanglement in three-qubit systems
(a) The transverse–distance measure \(\mu (\psi )\) introduced in (21) gives 0 for separable states and 1 for the GHZ–state. In addition, this also gives 0 for bi-separable states, so it discriminates bi-separability from genuine entanglement. Notably, \(\mu\) gives the same value as \(\xi\) for the W–state, which confirms that \(\vert W \rangle\) is \(\xi = \mu = 1/3\) distant from \(\vert GHZ \rangle\). (b) Regions of constant measure \(\mu (\psi ) = \mu _0\) for \(\mu _0 = 4/5\) (closest to vertex G) and \(\mu _0 = 1 - \sqrt{13}/5\) (closest to vertex S).
