Internal homogenization: effective permittivity of a coated sphere
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Updated: May 16, 2026

Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors
Published on: January 29, 2013
Uday K Chettiar1, Nader Engheta
1Department of Electrical and Systems Engineering, University of Pennsylvania, 200 South 33rd Street, Philadelphia, Pennsylvania 19104, USA. chettiar@seas.upenn.edu
Abstract:
The concept of internal homogenization is introduced as a complementary approach to the conventional homogenization schemes, which could be termed as external homogenization. The theory for the internal homogenization of the permittivity of subwavelength coated spheres is presented. The effective permittivity derived from the internal homogenization of coreshells is discussed for plasmonic and dielectric constituent materials. The effective model provided by the homogenization is a useful design tool in constructing coated particles with desired resonant properties.
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