Conditions for photonic bandgaps in two-dimensional materials

Abstract

Conditions that define the spectral location of bandgaps in the quasi-transverse magnetic surface plasmon polariton modal dispersion for 2D/quasi-2D materials with a tensor response function, embedded in a simple isotropic medium, are obtained. In the isotropic case, transverse magnetic surface plasmon polariton modes propagate if the surface conductivity is inductive. However, in the anisotropic case considered here, we find that quasi-transverse magnetic modes are supported by surfaces with an inductive effective conductivity seen by the wave along the direction of propagation (written as a weighted sum of the diagonal elements). Examples of natural anisotropic 2D/quasi-2D materials are presented to demonstrate the effectiveness of the method.