Final answer:
Phosphorescence is the delayed emission of light by materials that have absorbed energy and entered metastable states. This effect is used in glow-in-the-dark objects and in thermoluminescence for dating antiquities. It is distinct from stimulated emission, which is the basis for laser operation.
Step-by-step explanation:
The delayed emission of light from a stimulated material is known as phosphorescence. This phenomenon occurs when certain materials, like phosphorescent substances, absorb energy and enter metastable states with longer lifetimes before releasing that energy as visible light. This can be observed in glow-in-the-dark objects, which have materials that absorb light and then emit it slowly over time. An interesting application of this effect is thermoluminescence, where the slow release of light from materials, such as fired ceramics, can be used to date antiquities. Lasers utilize a related concept known as stimulated emission, where an excited electron drops back to a lower energy level and emits a photon, which can then stimulate the emission of additional photons from other excited atoms.