The Optogalvanic effect is the change in the
conductivity
Conductivity may refer to:
*Electrical conductivity, a measure of a material's ability to conduct an electric current
**Conductivity (electrolytic), the electrical conductivity of an electrolyte in solution
**Ionic conductivity (solid state), elec ...
of a
gas discharge Electric discharge in gases occurs when electric current flows through a gaseous medium due to ionization of the gas. Depending on several factors, the discharge may radiate visible light. The properties of electric discharges in gases are studied ...
induced by a light source (typically a
laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The fir ...
). This effect has found many applications in
atomic spectroscopy
Atomic spectroscopy is the study of the electromagnetic radiation absorbed and emitted by atoms. Since unique elements have characteristic (signature) spectra, atomic spectroscopy, specifically the electromagnetic spectrum or mass spectrum, is appl ...
and laser stabilization.
Introduction
In general, light will couple to atomic transitions if the energy difference between atomic levels is in resonance with some of the frequencies of the incoming light, thereby exchanging energy and momentum. In a gas discharge, the gaseous medium is affected by light on resonance with the atoms or molecules in the gas, thus creating a new balance in the energetic properties of the medium. Since the medium consists of charged particles, it is not surprising that also its electrical properties change.
References
Physical phenomena
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