Understanding the dynamics of light-meta structure interactions using skin-depth engineering (Conference Presentation)

Traditionally, geometrical factors have not played an important role in determining the distribution of current across conducting boundaries. Typically, the classical skin depth expression is used to estimate currents within the volume. We have developed a novel geometry-based framework which describes current distributions within the volume of structures which allows us to engineer skin depth using boundary shapes. A more accurate knowledge of current densities is an important degree of freedom to design and analyze meta-structures and their interactions. Our approach is grounded in a rigorous analysis of electromagnetic wave scattering from shell structures for which the importance of geometrical parameters in the expressions for skin depth to accurately describe interactions has been confirmed. Starting from Maxwell’s equations, we have analyzed the temporal dynamics of electromagnetic interactions with meta-structures and their relationship to vector potentials. Individual wavelength or subwavelength sized meta-structures can be designed to localize the incident electromagnetic radiation and create a change in the local constitutive relations. Having an accurate determination of the current distribution within the volume of scattering structures plays an important role in designing and determining the effective constitutive parameters of 2D and 3D metamaterials. Combinations of materials with custom geometries suggest that this kind of skin depth engineering can lead to new families of linear and non-linear meta-atoms impacting imaging, harmonic generation, and the design of antennas and their shielding.