$Withionmove

When the system has ion to perform as drift-diffusion equations, we solve the time dependent drift-diffusion for slow ion move simulation. Since the ion moves may not be governed fermi-level concept. We simply treat is a tradiational drift-diffusion equations.

$\frac{\partial M_{ion}}{\partial t} = e\mu M_{ion} \vec{E} - q D_{M} \nabla M_{ion}$