population inversion

population inversion
a condition of matter in which more electrons are in a high energy state than in a lower energy state, as is required for the operation of a laser.
[1960-65]

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      in physics, the redistribution of atomic energy levels that takes place in a system so that laser action can occur. Normally, a system of atoms is in temperature equilibrium and there are always more atoms in low energy states than in higher ones. Although absorption and emission of energy is a continuous process, the statistical distribution (population) of atoms in the various energy states is constant. When this distribution is disturbed by pumping energy into the system, a population inversion will take place in which more atoms will exist in the higher energy states than in the lower.

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Universalium. 2010.

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  • Population inversion — In physics, specifically statistical mechanics, a population inversion occurs when a system (such as a group of atoms or molecules) exists in state with more members in an excited state than in lower energy states. The concept is of fundamental… …   Wikipedia

  • population inversion — užpildos apgrąža statusas T sritis fizika atitikmenys: angl. occupation inversion; population inversion vok. Besetzungsumkehrung, f rus. обращение заселённости, n pranc. inversion de population, f …   Fizikos terminų žodynas

  • population inversion — Physics. a condition of matter in which more electrons are in a high energy state than in a lower energy state, as is required for the operation of a laser. [1960 65] …   Useful english dictionary

  • threshold population inversion density — slenkstinis apgrąžinės užpildos tankis statusas T sritis radioelektronika atitikmenys: angl. threshold population inversion density vok. Inversionsschwellendichte, f rus. пороговая плотность инверсной заселённости, f pranc. seuil de densité de… …   Radioelektronikos terminų žodynas

  • saturation of the population inversion — apgrąžinės užpildos sotis statusas T sritis radioelektronika atitikmenys: angl. saturation of the population inversion vok. Inversionssättigung, f rus. насыщение инверсной населённости, n pranc. saturation de population inversée, f …   Radioelektronikos terminų žodynas

  • inversion de population — užpildos apgrąža statusas T sritis fizika atitikmenys: angl. occupation inversion; population inversion vok. Besetzungsumkehrung, f rus. обращение заселённости, n pranc. inversion de population, f …   Fizikos terminų žodynas

  • Inversion de population — En physique, notamment en physique statistique, une inversion de population se produit lorsqu un système (à trois niveaux d énergie minimum) comme un groupe d atomes ou molécules, se trouve dans un état dans lequel la majorité des éléments sont… …   Wikipédia en Français

  • occupation inversion — užpildos apgrąža statusas T sritis fizika atitikmenys: angl. occupation inversion; population inversion vok. Besetzungsumkehrung, f rus. обращение заселённости, n pranc. inversion de population, f …   Fizikos terminų žodynas

  • seuil de densité de population inversée — slenkstinis apgrąžinės užpildos tankis statusas T sritis radioelektronika atitikmenys: angl. threshold population inversion density vok. Inversionsschwellendichte, f rus. пороговая плотность инверсной заселённости, f pranc. seuil de densité de… …   Radioelektronikos terminų žodynas

  • saturation de population inversée — apgrąžinės užpildos sotis statusas T sritis radioelektronika atitikmenys: angl. saturation of the population inversion vok. Inversionssättigung, f rus. насыщение инверсной населённости, n pranc. saturation de population inversée, f …   Radioelektronikos terminų žodynas

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