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Screening of point charges in Si quantum dots

Alberto Franceschetti·M. Claudia Troparevsky
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Abstract

The screening of point charges in hydrogenated Si quantum dots ranging in diameter from 10 A to 26 A has been studied using first-principles density-functional methods. We find that the main contribution to the screening function originates from the electrostatic field set up by the polarization charges at the surface of the nanocrystals. This contribution is well described by a classical electrostatics model of dielectric screening.

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Alberto Franceschetti, M. Claudia Troparevsky. 2005-08-16. Screening of point charges in Si quantum dots. https://doi.org/10.1103/physrevb.72.165311

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