Nanopatterned hard/soft bilayer magnetic antidot arrays with long-range periodicity

•The antidots have 40 nm diameter and square or hexagonal symmetry.•Long-range periodicity greatly enhances magnetic coercivity and domain-wall pinning.•Square symmetry results in inhomogeneous magnetic nano-structure.•A high density of immobile super-domain walls is observed at square symmetry arrays.•Hexagonal symmetry arrays show a homogeneous magnetic configuration.