Quantum Discord — Bipartite Separable States

Quantum discord D(A|B) = I(A;B) - J(A|B) captures quantum correlations beyond entanglement. Even separable (unentangled) states can have nonzero discord. Explore the discord landscape for two-qubit X-states.

X-State Parameters

Purity p: 0.8 Coherence c: 0.3 Asymmetry a: 0.0 X-param x₁₄: 0.2

Correlations

Concurrence C: —

Entanglement E: —

Mutual info I: —

Discord D: —

Classical corr J: —

D(A|B) = I(A;B) - J(A|B)
I = S(ρ_A)+S(ρ_B)-S(ρ_AB)
J = max measurement
Discord ≥ 0 always

Quantum Discord — Bipartite Quantum Correlations

X-State Parameters

Correlations