Abstract
The rise of Mie-resonant photonics offers a powerful route to tailor electromagnetic wave-matter interactions for efficient wave manipulation. Although Mie-resonant metamaterials, typically consisting of arrays of subwavelength high-refractive-index particles, have been widely investigated, their performance in the near field is fundamentally constrained by their effective (spatially averaged) response. Here, departing from the standard effective-medium paradigm, we introduce an alternative mechanism for realizing artificial magnetism. By harnessing the unique properties of Mie resonances, we demonstrate that a high-index multilayered dielectric sphere can be tailored to exhibit the desired magnetic behavior for manipulating waves at deeply subwavelength scales, including negative, positive, and near-zero permeability. We validate our approach through full-wave numerical simulations and experiments in the microwave range. The versatility of our approach paves the way for designing novel photonic elements with applications ranging from magnetic resonance imaging to advanced nanophotonics.