Snapshots of the vertically integrated dust density distribution for evolutionary times of 0.1, 1 and 3 Myr. The planet is located at 60 au and the planet-to-star mass ratio is 10^-3. The horizontal dashed lines represent the particle sizes corresponding to a size parameter of x = 2πa/λ ~ 1 considering λ = 0.87 mm, λ = 1.3 mm, and λ = 3.1 mm. If the dominant grain size at a certain disk location is less than ~λ/ 2π, there is significant polarization in scattered light.