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Oppenheimer had predicted [14] that the field-induced tunneling of electrons from atoms (the effect now called field ionization) would have this i(V) dependence, had found this dependence in the published experimental field emission results of Millikan and Eyring, [10] and proposed that CFE was due to field-induced tunneling of electrons from ...
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 ...
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
In a group of such atoms, if the number of atoms in the excited state is given by N 2, the rate at which stimulated emission occurs is given by = = where the proportionality constant B 21 is known as the Einstein B coefficient for that particular transition, and ρ(ν) is the radiation density of the incident field at frequency ν. The rate of ...
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.
Thermionic emission, the liberation of electrons from an electrode by virtue of its temperature Schottky emission, due to the: Schottky effect or field enhanced thermionic emission; Field electron emission, emission of electrons induced by an electrostatic field
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.
Quantum tunnelling is among the central non-trivial quantum effects in quantum biology. [33] Here it is important both as electron tunnelling and proton tunnelling. Electron tunnelling is a key factor in many biochemical redox reactions (photosynthesis, cellular respiration) as well as enzymatic catalysis.