exciton

exciton
/ik suy"ton, ek"si ton'/, n. Physics.
a localized, mobile excited state of a crystal, consisting of an electron and a hole bound together.
[1935-40; EXCIT(ED) or EXCIT(ATION) + -ON1]

* * *

      the combination of an electron and a positive hole (an empty electron state in a valence band), which is free to move through a nonmetallic crystal as a unit.

      Because the electron and the positive hole have equal but opposite electrical charges, the exciton as a whole has no net electrical charge (though it transports energy). This makes excitons difficult to detect, but detection is possible by indirect means.

      When an electron in an exciton recombines with a positive hole, the original atom is restored, and the exciton vanishes. The energy of the exciton may be converted into light when this happens, or it may be transferred to an electron of a neighbouring atom in the solid. If the energy is transferred to a neighbouring electron, a new exciton is produced as this electron is forced away from its atom.

* * *


Universalium. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • EXCITON — EXCI Quasi particule utilisée en physique quantique pour décrire la propagation de l’énergie dans un diélectrique ou dans un semiconducteur par le mécanisme du transfert graduel (d’une molécule à la suivante). L’énergie transférée est une énergie …   Encyclopédie Universelle

  • exciton — excitón s. m., pl. excitóni Trimis de siveco, 10.08.2004. Sursa: Dicţionar ortografic  EXCITÓN s. m. particulă fictivă asociată unei stări de excitaţie care se propagă prin masa unui corp cristalin. (< germ. Exciton) Trimis de raduborza,… …   Dicționar Român

  • éxciton — s. m. [Física] Par composto por um elétron e por um buraco num semicondutor ou num isolante. • [Brasil] Plural: excítones e éxcitons.   ‣ Etimologia: inglês excitão   ♦ Grafia em Portugal: excitão …   Dicionário da Língua Portuguesa

  • exciton — [ek sī′tän, ek′sə tän΄] n. a localized, electrically neutral, excited state that allows the transfer of energy but not electric charge through a semiconductor, insulator, etc., as an electron bound to a positive hole excitonic adj …   English World dictionary

  • Exciton — This page is about the quasiparticle. Exciton is also the title of a single by IDM composer Squarepusher. An exciton is a bound state of an electron and an imaginary particle called an electron hole in an insulator or semiconductor, and such is a …   Wikipedia

  • Excitón — Un excitón es una cuasipartícula (o excitación elemental) de los sólidos formada por un electrón y un hueco ligados a través de la interacción coulombiana. Se da únicamente en semiconductores y aislantes. Una forma de entender la formación del… …   Wikipedia Español

  • Exciton — Un exciton est, en physique, une quasi particule que l on peut voir comme une paire électron trou liée par des forces de Coulomb. Une analogie souvent utilisée consiste à comparer l électron et le trou respectivement à l électron et au proton d… …   Wikipédia en Français

  • Exciton — eksitonas statusas T sritis fizika atitikmenys: angl. exciton vok. Exciton, n; Exziton, n rus. экситон, m pranc. exciton, m …   Fizikos terminų žodynas

  • exciton — eksitonas statusas T sritis fizika atitikmenys: angl. exciton vok. Exciton, n; Exziton, n rus. экситон, m pranc. exciton, m …   Fizikos terminų žodynas

  • Exciton — Ein Exziton (engl. exciton) ist ein gebundener Zustand von Elektron und Loch in einem Isolator bzw. einem Halbleiter. Es ist somit eine elementare Anregung des Festkörpers. Es ist wie ein Phonon oder ein Polaron ein Quasiteilchen. Ein Exziton… …   Deutsch Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”