Scientific terminology laser is commonly written in small letters. It has even produced secondary acronyms such as LASIK (Laser-ASsisted in Situ Keratomileusis). A related acronym and neologism maser (Microwave Amplification by Stimulated Emission of Radiation) is much less known. Nevertheless, it is commonly written in small letters. On the contrary, acronym SPASER (Surface Plasmon Amplification by Stimulated Emission of Radiation) is capitalized. Many scientific acronyms or abbreviations reflect the artistic sense of their creators, e.g., etc. (see also List of astronomy acronyms). Scientific terminology Scientific terminology is the part of the language that is used by scientists in the context of their
Stimulated emission of energy levels 1 and 2, respectively. The intensity (in watts per square meter) of the stimulated emission is governed by the following differential equation: as long as the intensity "I"("z") is small enough so that it does not have a significant effect on the magnitude of the population inversion. Grouping the first two factors together, this equation simplifies as where is the "small-signal gain coefficient" (in units of radians per meter). We can solve the differential equation using separation of variables: Integrating, we find: or where The saturation intensity "I" is defined as the input intensity at which the