Quantifying mixed-state quantum entanglement by optimal entanglement witnesses
Quantifying mixed-state quantum entanglement by optimal entanglement witnesses
We develop an approach of quantifying entanglement in mixed quantum states by the optimal entanglement witness operator. We identify the convex set of mixed states for which a single witness provides the exact value of an entanglement measure and show that the convexity, properties, and symmetries of entanglement or of …