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Care is necessary because in some contexts (e.g. spacecraft engineering), the name "field emission" is applied to the field-induced emission of ions (field ion emission), rather than electrons, and because in some theoretical contexts "field emission" is used as a general name covering both field electron emission and field ion emission.
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 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.
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.
Notably, the effect can be either heating or cooling of the surface emitting the electrons, depending upon the energy at which they are supplied. [4] Above the Nottingham inversion temperature, the emission energy exceeds the Fermi energy of the electron supply and the emitted electron carries more energy away from the surface than is returned by the supply of a replacement electron, and the ...
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.
The Schottky effect or field enhanced thermionic emission is a phenomenon in condensed matter physics named after Walter H. Schottky. In electron emission devices, especially electron guns, the thermionic electron emitter will be biased negative relative to its surroundings. This creates an electric field of magnitude F at the
Classically, the electron would either transmit or reflect with 100% certainty, depending on its energy. In 1928 J. Robert Oppenheimer published two papers on field emission, i.e. the emission of electrons induced by strong electric fields.