S. Scandolo, ICTP

Lesson 12 (Crystals: the free electron model)

In this short lecture, the professor discusses the simplest model for crystals, when the electrons don't feel the potential of the atoms at all. The assumption the model makes is that the easily polarizable electron cloud can screen the atoms effectively. In this limit, when V -> 0, the band structure is quite simple: the Fermi energy can be expressed as a function of the electron density.