Base Information
Volume
V48 - N2 / 2015 International Year of Light
Reference
109-113
DOI
http://dx.doi.org/10.7149/OPA.48.2.109
Language
Spanish / Español
Keywords
Spontaneous emission, stimulated emission, absorption, laser, optical cavity.
Abstract
When we talk about the laser, we talk about light emitted in a stimulated way which is the light directly visible. However, processes of spontaneous emission occur at the same time. Light emitted spontaneously can be easily observed by removing the casing of a Helium Neon laser. The simultaneous occurrence of processes of spontaneous and stimulated emission is an unshakeable law of nature, even if processes of the second type predominate in the laser. A simple experience allows us to carry out a rough calculation of the ratio between the two types of processes.
References
Einstein, Albert. 1917. "On the quantum theory of radiation,"Physikalische Zeitschrift 18: 121-128 [in German]. English translation in Barnes, Frank S. (ed.). Laser Theory. IEEE Press, New York (1972).
Didier Dangoisse, Daniel Hennequin, Veronique Zehnlé-Dhaoui. Les lasers. Dunod, Paris. (1998).