We developed an open-source Plane Wave Expansion Method solver using Python and a custom Tkinter library to solve a design oriented problem of photonic crystal dispersion for known classical examples, custom geometries, and symmetries. Such structures are capable of light confinement, omnidirectional reflection, beam collimation and negative refraction. We dive deeper into the diagonally anisotropic photonic crystals, whose Plane Wave Expansion algorithm is directly embedded in the application. The user interface is present in the developer’s repository link: https://github.com/ZenTunturi/ZenBand.
Zinkevičius et al. (2026) studied this question.