Isotropic magnetic response of silicon carbide microspheres at mid-infrared wavelength

Base on the Lorentz–Lorenz formula, magnetic response in metamaterial composed of randomly dispersive SiC microspheres is demonstrated theoretically around 13μm mid-infrared wavelength. By adjusting the microspheres volume filling fraction the permeabilities both less than one and more than one can be obtained. Through parameters optimization, isotropic negative permeability is represented. Electromagnetic simulation shows the mechanism for magnetic effects and negative permeability in SiC microspheres.