Spinodal Decomposition — Cahn-Hilliard Coarsening

Phase separation via CH equation: ∂φ/∂t = M∇²[f'(φ) − κ∇²φ] — coarsening follows t^(1/3)

Free Energy

Simulation

Step: 0

Theory

Cahn-Hilliard equation:
∂φ/∂t = M∇²[f'(φ)−κ∇²φ]

Free energy: f(φ)= τφ²/2+φ⁴/4
Spinodal: τ < 0 → unstable

Linear instability: σ(q) = −Mq²(τ+κq²)
Max growth: q* = √(|τ|/2κ)

Coarsening: ⟨R(t)⟩ ~ t^(1/3)
Lifshitz-Slyozov-Wagner (LSW) theory