Tunable Photonic Band Gaps in Two-Dimensional Bravais–Moiré Photonic Crystal Composed of High-Tc Superconductors

In this study, we perform a theoretical study of light propagation properties in two-dimensional square photonic crystals (PCs) following Bravais–Moiré (BM) patterns composed of copper oxide high-temperature superconductors (HTSCs). The BM PCs are made of cylindrical cores formed from the combination of two square Bravais lattices. The Moiré pattern forms due to a commensurable rotation of one of these lattices with respect to the other. The dielectric function of the superconducting material is modeled by the two-fluid Gorter–Casimir theory. We report on the corresponding gap, the mapping as a function of the radius of dielectric cores, as well as the dispersion relations of TM modes for BM PCs and for the waveguide system built of defect lines within such a crystal. The BM PCs were composed of copper oxide HTSCs, which exhibit large tunability in terms of temperature.