Figure 4From: Ripple coarsening on ion beam-eroded surfacesHeight profiles and distribution of the surface gradient angles of Figure 3f. The profiles are along the triangular depressions (a) and in region where only ripples exist (b). The arrows indicate the direction of the ion beam incidence. The angular distribution are evaluated for the entire AFM image (c) and in the region where only ripples occur (d). α < 0° correspond to the upstream side and α > 0° to the downstream side of the facets.Back to article page