Density of photonic states in aperiodic structures

Periodicity is usually assumed to be the necessary and sufficient condition for formation of band gaps, i.e., energy bands with a suppressed density states. Here, we check this premise by analyzing gap properties three structures that differ in degree periodicity ordering. We consider photonic crystal, disordered lattice, ordered but nonperiodic quasicrystalline structure. A real-space metric allows us compare these different structures. Using metric, reveal lattice quasicrystal can attributed same group material examine their states both theoretically experimentally. The analysis reveals despite dramatically degrees periodicity, crystal structure demonstrate an almost similar suppression Our results give new insight into physical mechanisms resulting gaps.