Photonic band structures

Photonic band structures describe how light waves behave inside materials with a repeating pattern, like a crystal. Similar to how electrons move through the atomic lattice in solids, photons (light particles) experience allowed and forbidden energy ranges—called bands—depending on the material's structure. This results in certain wavelengths of light being transmitted, reflected, or blocked. These structures enable control over light, leading to applications like efficient lasers, optical filters, or cloaking devices. Essentially, photonic band structures map out how light of different energies interacts with a patterned material at a microscopic level.