Demonstrating the dynamics of electron-light interaction originating from first principle

With the highest possible spatial resolution of less than a millionth of a millimeter, electron microscopes make it possible to study the properties of materials at the atomic level and thus demonstrate the realm of quantum mechanics. Quantum-physical fundamentals can be studied particularly well by the interactions between electrons and photons. Excited with laser light, for example, the energy, mass or velocity of the electrons changes.