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Internal homogenization: effective permittivity of a coated sphere
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
Optics Express
|November 29, 2012
Summary
Internal homogenization offers a new method for analyzing coated spheres, complementing external approaches. This technique helps design particles with specific resonant properties by calculating effective permittivity.
Area of Science:
- Physics
- Materials Science
- Nanotechnology
Background:
- Conventional homogenization methods, termed external homogenization, are widely used.
- Analyzing subwavelength coated spheres requires advanced theoretical frameworks.
Purpose of the Study:
- Introduce internal homogenization as a novel approach.
- Present the theory for internal homogenization of coated spheres' permittivity.
- Explore its application in designing particles with tailored resonant properties.
Main Methods:
- Developed the theory for internal homogenization.
- Applied the theory to subwavelength coated spheres.
- Derived effective permittivity for core-shell structures.
Main Results:
- Introduced the concept of internal homogenization.
- Presented the theoretical framework for permittivity homogenization.
- Discussed effective permittivity for plasmonic and dielectric materials.
Conclusions:
- Internal homogenization is a valuable complementary technique.
- The derived effective model aids in designing coated particles.
- This approach facilitates the creation of particles with desired resonant characteristics.
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