Mie scattering by an anisotropic object. Part I. Homogeneous sphere

Area of Science:

• Electromagnetism
• Optics
• Materials Science

Background:

• Mie theory traditionally applies to isotropic spheres.
• Anisotropic materials exhibit complex electromagnetic responses.
• Diffraction by arbitrarily shaped anisotropic objects remains a challenge.

Purpose of the Study:

• To extend Mie theory for diffraction by anisotropic spheres.
• To develop a framework for analyzing electromagnetic fields in anisotropic media.
• To pave the way for a differential diffraction theory for 3D anisotropic objects.

Main Methods:

• Establishing a vector spherical harmonic expansion for electromagnetic fields.
• Applying this expansion to the problem of diffraction by an anisotropic sphere.
• Analyzing the specific case of uniaxial anisotropic materials.

Main Results:

• A generalized Mie theory for anisotropic spheres (with or without losses) is presented.
• The analysis is simplified for the specific case of uniaxial materials.
• The vector spherical harmonic expansion provides a robust mathematical framework.

Conclusions:

• The extended Mie theory successfully addresses diffraction by anisotropic spheres.
• This work lays the foundation for a differential diffraction theory for arbitrary 3D anisotropic objects.
• The findings are crucial for understanding light-matter interactions in complex anisotropic systems.