“Left-Handed” Magnetic Granular Composites
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We investigate the possibility of preparing left-handed materials in metallic magnetic granular composites. Based on the effective medium approximation, we show that by incorporating metallic magnetic nanoparticles into an appropriate insulating matrix and controlling the directions of magnetization of metallic magnetic components and their volume fraction, it may be possible to prepare a composite medium which is left handed for electromagnetic waves propagating in some special direction and polarization in a frequency region near the ferromagnetic resonance frequency. This composite may be easier to make on an industrial scale. In addition, its physical properties may be easily tuned by rotating the magnetization locally. The anisotropic characteristics of this material is discussed. The exactly solvable example of the multilayer system is used to illustrate the results of the effective medium calculation.
KeywordsWave Vector Incident Wave Poynting Vector Permeability Tensor Refract Wave
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