Photonic crystals are materials with periodic variation of refractive index on a scale comparable to the wavelength of light. In this experimental problem, we study the properties of photonic crystals based on porous films of anodic aluminum oxide (AAO). The structure of AAO porous films is a system of disjoint cylindrical channels with a diameter less than 50 nm located perpendicular to the film surface. Pore diameters change periodically with a period of about 200 nm.
The main effect studied in the experiment can be seen in the video https://photos.app.goo.gl/UiVkqnPALavJffe57. We look at the rainbow through a transparent photonic crystal. When we rotate the crystal, the dark stripe moves across the spectrum.
