Electrons in a crystal lattice: A simple computer model

A simple computer program is presented, well within the capability of sophomore students, which solves the Schrödinger equation for a ‘‘lattice’’ of up to 12 potential wells, and which demonstrates many features important in a discussion of semiconductor physics—energy bands, impurity states, amorphous effects, negative effective mass. The ability to present material like this to students computationally may well have a profound effect on what is taught in future physics curriculums.