Transform between the permeability and permittivity in the close-packed Ni nanoparticles

We report an anomalously electromagnetic resonance in a simple Ni nanoparticle/paraffin system. The resonance, caused by the near-field interaction of nanoparticles, appears at ∼16 GHz as decreasing the interparticle distance down to ∼11 nm. It is associated with an unusual energy transfer from the permeability to permittivity, resulting in the enhanced dielectric and weakened magnetic attenuations. These experimental results can be well modeled by a numerical simulation, evidencing the enhanced electrical filed distribution as decreasing the interaction distance. This study enables us to first realize the permeability-to-permittivity transform of electromagnetic wave in nanocomposites.