▎ 摘　　要

Topological properties of graphene with nanoholes are theoretically investigated in detail. It is revealed that two types of hole arrangements, honeycomb array and triangular array, give rise to two topologically distinct states. We give a concise two-step strategy for choosing array structures, where two types of Brillouin zone folding, corner-to-corner or corner-to-center, play crucial roles. The topological nontriviality is confirmed by interface states at a domain wall between the honeycomb and triangular hole arrays, which show a cross-shaped band structure resembling helical edge states in quantum spin Hall states. We also diagnose the topology of the states from the view point of the topological crystalline insulator and show that the parity index against the C-2 rotation is a key quantity. These findings indicate that nanotechnology-based geometrical design and manipulation are promising in exploration of topological phases of matter.