≈ Quantum discord: OD (PAB)=S(P)+min p s(pBliA-S(PAB Where S(p)=-Tr(plog2 p o Geometry measure of Quantum Discord min AB AB ZAB O e Where 2o is the set of zero-discord Entanglement of formation E(p)=min、E(v) (Pi 4 s where E(AB))=S(pA) H Ollivier and W.H. Zurek, PhysRevLett 88.017901 B. Dakic, V Vedral, and C. Brukner, Phys. Rev. Lett. 105, 190502❖ Quantum discord: ❖ Where ❖ Geometry measure of Quantum Discord: ❖ Where is the set of zero-discord. ❖ Entanglement of formation: ❖ where ( ) ( )   min ( ) ( ) A i A A AB A i B A AB i QD S p S i S      = + −  S Tr (   ) = − ( log2 ) ( ) 0 2 min AB DA AB AB AB      = − 0 H. Ollivier and W. H. Zurek, PhysRevLett.88.017901 B.Dakic,V.Vedral, and C. Brukner,Phys. Rev. Lett. 105, 190502 ( )   ( ) , min i i AB i AB i AB p E p E    = ( ) ( ) i i E S   AB A =