When light strikes a material, electrons may be ejected from the material. This is called the photoelectric effect, and it’s the basis for many different technologies that convert light energy into electrical energy to generate current. In addition, the photoelectric effect is useful to scientists studying novel materials.
There are many ways atoms can arrange microscopically to form crystalline materials. Interestingly, materials created from different arrangements of the same atoms may exhibit completely different physical and chemical properties. A method called thin film epitaxy allows scientists not only to fine-tune the properties of known materials, but also to generate completely new materials with structures and properties not found in nature.