Tunable bilayer photonic quasicrystal

Abstract

The unique properties of incommensurate two-dimensional bilayer structures, a wide class of optical materials, are largely determined by the relative rotation angle between the layers. Here, we present a comprehensive theoretical analysis of the optical properties of a dodecagonal quasicrystal based on twisted bilayer material with hexagonal layers rotated by 30°. By assuming that the quasicrystal is tuned to the Bragg condition, we calculate its reflectance spectra and reveal the Wood anomalies therein, which are characteristics of structures with a long-range order. It is also shown that the reflectance spectra can be dynamically controlled by the external electric field applied perpendicular to the quasicrystal's surface. This feature can be used to create tunable photonic devices such as optical switches and sharp M-shape bandpass filters.