# Photonic crystal slab band structure calculation
In this example, we simulate a photonic crystal slab consisting of a square lattice of air holes in a dielectric slab. Our goal is to compute the band structure of this photonic crystal slab, as found in Shanhui Fan and J. D. Joannopoulos, “Analysis of guided resonances in photonic crystal slabs,” Phys. Rev. B 65, 235112 (2002) (opens new window).
To this end, we excite the structure with several PointDipole (opens new window) sources, and we measure the response with several FieldTimeMonitor (opens new window) monitors. We excite modes with a fixed Bloch wavevector by using Bloch boundary conditions. We then use the ResonanceFinder (opens new window) to find the resonant frequencies. By sweeping the Bloch wavevector, we obtain the full band structure of the photonic crystal slab.
To view the full example in Python, please click here (opens new window).