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When the emitter is so sharp that atomic-level detail cannot be neglected, and/or the tunneling barrier is thicker than the emitter-apex dimensions, then a more sophisticated approach is desirable. As noted at the beginning, the effects of the atomic structure of materials are disregarded in the relatively simple treatments of field electron ...
For example, excited Cs-vapours in thermionic converters form clusters of Cs-Rydberg matter which yield a decrease of collector emitting work function from 1.5 eV to 1.0–0.7 eV. Due to long-lived nature of Rydberg matter this low work function remains low which essentially increases the low-temperature converter’s efficiency.
For example, excited Cesium (Cs) vapors in thermionic converters form clusters of Cs-Rydberg matter which yield a decrease of collector emitting work function from 1.5 eV to 1.0–0.7 eV. Due to long-lived nature of Rydberg matter this low work function remains low which essentially increases the low-temperature converter's efficiency.
Emission coefficient is a coefficient in the power output per unit time of an electromagnetic source, a calculated value in physics. The emission coefficient of a gas varies with the wavelength of the light. It has unit m⋅s −3 ⋅sr −1. [18]
Next, suppose we have a material that violates Kirchhoff's law when integrated, such that the total coefficient of absorption is not equal to the coefficient of emission at a certain , then if the material at temperature is placed into a Hohlraum at temperature , it would spontaneously emit more than it absorbs, or conversely, thus ...
In atomic, molecular, and optical physics, the Einstein coefficients are quantities describing the probability of absorption or emission of a photon by an atom or molecule. [1] The Einstein A coefficients are related to the rate of spontaneous emission of light, and the Einstein B coefficients are related to the absorption and stimulated ...
The exact reverse of radiative recombination is light absorption. For the same reason as above, light with a photon energy close to the band gap can penetrate much farther before being absorbed in an indirect band gap material than a direct band gap one (at least insofar as the light absorption is due to exciting electrons across the band gap).
A single-photon source (also known as a single photon emitter) [1] is a light source that emits light as single particles or photons. Single-photon sources are distinct from coherent light sources ( lasers ) and thermal light sources such as incandescent light bulbs .