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According to ISO 13600, an energy carrier is either a substance or a phenomenon that can be used to produce mechanical work or heat or to operate chemical or physical processes. [1] It is any system or substance that contains energy for conversion as usable energy later or somewhere else. This could be converted for use in, for example, an ...
From the kinetic theory of gases, [20] thermal conductivity of principal carrier i (p, e, f and ph) is =,, where n i is the carrier density and the heat capacity is per carrier, u i is the carrier speed and λ i is the mean free path (distance traveled by carrier before an scattering event). Thus, the larger the carrier density, heat capacity ...
There are several mechanisms by which minority carriers can recombine, each of which subtract from the carrier lifetime. The main mechanisms that play a role in modern devices are band-to-band recombination and stimulated emission, which are forms of radiative recombination, and Shockley-Read-Hall (SRH), Auger, Langevin, and surface recombination, which are forms of non-radiative recombination.
Carrier mobility in semiconductors is doping dependent. In silicon (Si) the electron mobility is of the order of 1,000, in germanium around 4,000, and in gallium arsenide up to 10,000 cm 2 /(V⋅s). Hole mobilities are generally lower and range from around 100 cm 2 /(V⋅s) in gallium arsenide, to 450 in silicon, and 2,000 in germanium. [1]
In electromagnetism, current density is the amount of charge per unit time that flows through a unit area of a chosen cross section. [1] The current density vector is defined as a vector whose magnitude is the electric current per cross-sectional area at a given point in space, its direction being that of the motion of the positive charges at this point.
Carrier generation describes processes by which electrons gain energy and move from the valence band to the conduction band, producing two mobile carriers; while recombination describes processes by which a conduction band electron loses energy and re-occupies the energy state of an electron hole in the valence band.
A growing body of evidence has shown links between cancer and drinking alcohol. In a warning Friday, U.S. Surgeon General Vivek Murthy said cancer risk increases with the number of drinks, but ...
The highest DC power efficiency occurs when the time delta between PA Enable and the RF signal is minimized, but a short delay can exacerbate transient effects on the RF signal. Because the power-up/power-down operation of the PA can cause transient and thermal effects that degrade transmitter performance, another metric called Dynamic EVM is ...