Movie S1.

The concept of the recurrence map can be more clearly understood by using an animated description of the dynamics. Our animation shows the time evolution of a particle trajectory and connects it to the corresponding dynamics in a recurrence map. In the movie, the three panels from the left show the trajectory in multiple pillars, the trajectory in a unit cell, and the recurrence map, respectively. Here, Np= 5 and the pillar diameter D0 is 200 nm. The pillar-to-pillar distance (Dx=Dy) is 400 nm, so that the ratio (D0/Dy) is 0.5. The long trajectory is composed of eight total transition segments starting from 90% of the pillar gap (η0= 0.9). For the particle with radius larger than the critical diameter (ηc−), the trajectory is similar to that of the small particle until it veers around the pillar for the first time. However, because of the shift of the center of particle by the pillar repulsion, it cannot veer around the pillar and bumps on the post surface. After it follows the closest possible streamline to the separatrix line, it ends up to the same initial position [the directional locking (21)]. The animation in the middle shows this transition by overlaid trajectories inside a unit cell. In the recurrence map, the mapping f intersects the identity function (y=x), which becomes a fixed point in the dynamics. Here, the blue circle indicates the initial position at the inlet, and the red circle indicates the final position at the outlet. Movie S1