Quasicrystal-related mosaics with periodic lattices interlaid with aperiodic tiles.

Quasicrystals, which have long-range orientational order without translational symmetry, are incompatible with the theory of conventional crystals, which are characterized by periodic lattices and uniformly repeated unit cells. Reported here is a novel quasicrystal-related solid state observed in two Al-Cr-Fe-Si alloys, which can be described as a mosaic of aperiodically distributed unit tiles in translationally periodic structural blocks. This new type of material possesses the opposing features of both conventional crystals and quasicrystals, which might trigger wide interest in theory, experiments and the potential applications of this type of material.