Source: wikibot/resonance-fluorescence
= Resonance fluorescence
{wiki=Resonance_fluorescence}
Resonance fluorescence is a process in which a photon with energy matching the energy difference between two quantum states of a system (such as an atom or molecule) is absorbed, promoting the system to an excited state. After a brief period in the excited state, the system returns to its lower energy state, emitting a photon in the process.