Geometrical quantum discord and negativity of two separable and mixed qubits
Liu Tang-Kun †, Liu Fei, Shan Chuan-Jia, Liu Ji-Bing
       

The E(t) for P = 0 against the scaled time gt. In panels (a)–(d), ∣ α ∣ = 1 , 5 , 10 , 15 , respectively.