There has been much interest in photonic and spectroscopic devices that are
useful for controlling transmission and reflection coefficients such as multilayer
thin films, photonic crystals, and various Bragg structures in the form of
molds or multilayer thin films.
Photonic crystals is a low-loss periodic medium with periodic changes of
refractive index, which is used to control the light.
Theoretically, Photonic crystals can be studied using Maxwell equations, but
it’s difficult to find a general analytical
solution for these equations, since we
are dealing with vectors. So we resort to the numerical solutions for Maxwell’s
equations to calculate the reflection and transmission coefficients and the
Photonic band gap.
