In this unit, we have explored the physical properties of various luminescent materials and devices including glow-in-the-dark toothbrushes; fireflies; light sticks; Lifesavers®; and fluorescent lamps and objects. The quantum model of energy band diagrams explained these materials and devices. The development of this comprehensive model started with atoms of gases to explain the properties of gas lamps and ended with the atoms of solids with impurities to explain luminescent materials and the fluorescent lamp. We could say that the quantum model is very “cool” because it allows us to see everyday phenomena in a new “light” and gives us a deeper understanding and appreciation for the various processes in which matter emits light.
