A Triangle Governs Genuine Tripartite Entanglement

Abstract

A previously overlooked constraint for the distribution of entanglement in three-qubit systems is exploited for the first time and used to reveal a new genuine tripartite entanglement measure. It is interpreted as the area of a so-called concurrence triangle and is compared with other existing measures. The new measure is found superior to previous attempts for different reasons. A specific example is illustrated to show that two tripartite entanglement measures can be inequivalent due to the high dimensionality of the Hilbert space.

Entanglement on Orbits

“…The W class has only three free parameters and is much smaller compared to the GHZ class. A few tripartite entanglement measures have been studied based on the SLOCC-equivalence classification (examples are [7,8]).…”