Atomic-scale dielectric permittivity profiles in slabs and multilayers
نویسندگان
چکیده
A recently developed theory of atomic-scale local dielectric permittivity has been used to determine the position dependent permittivity profiles of a few nanoscale insulator surfaces and multilayers. Specifically, slabs containing single-component Si, polymer, and SiO2 and two-component Si-SiO2 and polymer-SiO2 systems of technological importance have been studied. The present approach indicates that the local permittivity is generally enhanced at the surfaces and/or interfaces, and that it approaches the corresponding bulk values in the interior of each component. This simple method of determining the position-dependent dielectric permittivity profiles can be used to study the impact of atomic level disorder and defects on dielectric properties.
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