| In this article, we examine an effective-medium theory (EMT) within the coherent-potential approximation, which is suitable to retrieve the effective permittivityεeff and permeabilityμeff of the anisotropic magnetic metamaterials consisting of the ferrite rods. The anisotropy originates from the gyromagnetic property of the ferrite material whose permeability is a ten-sor with nonzero off-diagonal components. We calculate the photonic band structure within multiple-scattering method(MST), the effective parametersεeff,μeff and wave vectorκeff with EMT, and the results of the two methods are perfect in agreement in the long wavelength limit. So our theory is confirmed. The electric field patterns of the materials composed of ordered, disordered ferrite rods and the effective ones are simulated, which are still in agree-ment with each other, our EMT is confirmed to be powerful again. At the time, we find it is necessary to consider the anisotropy to retrieve the effective constitutive parameters accu-rately. The EMT for anisotropic medium can be translated into the one for isotropic medium by approximation and making the off-diagonal be zero. EMT can be used widely such as electromagnetic black hole, light deflexion and so on, their materials'effective constitutive parameters are obtained by EMT. In addition, we also discussed some basic theories which are used in our research, such as Mie theory and multiple scattering method.
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