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Field electron emission, also known as field emission (FE) and electron field emission, is emission of electrons induced by an electrostatic field. The most common context is field emission from a solid surface into a vacuum .
Stimulated emission was a theoretical discovery by Albert Einstein within the framework of the old quantum theory, wherein the emission is described in terms of photons that are the quanta of the EM field. [5] [6] Stimulated emission can also occur in classical models, without reference to photons or quantum-mechanics.
In physics, electron emission is the ejection of an electron from the surface of matter, [1] or, ... emission of electrons induced by an electrostatic field; Devices
Absolute methods employ electron emission from the sample induced by photon absorption (photoemission), by high temperature (thermionic emission), due to an electric field (field electron emission), or using electron tunnelling. Relative methods make use of the contact potential difference between the sample and a reference electrode.
Lothar [note 1] Wolfgang Nordheim (November 7, 1899, Munich – October 5, 1985, La Jolla, California) was a German-born Jewish American theoretical physicist.He was a pioneer in the applications of quantum mechanics to solid-state problems, such as thermionic emission, work function of metals, [1] field electron emission, rectification in metal-semiconductor contacts and electrical resistance ...
Stimulated emission (also known as induced emission) is the process by which an electron is induced to jump from a higher energy level to a lower one by the presence of electromagnetic radiation at (or near) the frequency of the transition. From the thermodynamic viewpoint, this process must be regarded as negative absorption.
In this regime, the combined effects of field-enhanced thermionic and field emission can be modeled by the Murphy-Good equation for thermo-field (T-F) emission. [35] At even higher fields, FN tunneling becomes the dominant electron emission mechanism, and the emitter operates in the so-called "cold field electron emission (CFE)" regime.
The rate of spontaneous emission (i.e., the radiative rate) can be described by Fermi's golden rule. [17] The rate of emission depends on two factors: an 'atomic part', which describes the internal structure of the light source and a 'field part', which describes the density of electromagnetic modes of the environment.