Electromagnetic energy in multilayered spherical particles.

Area of Science:

• Electromagnetism
• Materials Science
• Nanophotonics

Background:

• Understanding electromagnetic energy distribution in complex structures is crucial for designing advanced optical devices.
• Multilayered spheres, particularly metallo-dielectric ones, exhibit unique optical properties relevant to plasmonics and metamaterials.

Purpose of the Study:

• To derive exact analytic expressions for electromagnetic energy density and total stored energy in multilayered spheres.
• To provide explicit formulas for lossless core and shell cases.
• To demonstrate the application of the method to electric field enhancement in silica-gold spheres.

Main Methods:

• Development of a compact recursive transfer-matrix method for general multilayered spheres.
• Inclusion of magnetic media in the theoretical framework.
• Validation through examples of electric field enhancement in specific metallo-dielectric structures.

Main Results:

• Exact analytic expressions for electromagnetic energy radial density (inside and outside).
• Exact analytic expressions for total electromagnetic energy stored in cores and shells.
• Demonstration of electric field enhancement in silica-gold multilayered spheres.

Conclusions:

• The transfer-matrix method provides a robust framework for calculating electromagnetic energy in multilayered spherical systems.
• The derived expressions are applicable to both dielectric and magnetic materials.
• The study offers a valuable theoretical and computational tool for research in nanophotonics and metamaterials.