In this paper, a magnetically tunable metamaterial is proposed and studied. The metamaterial is based on the combination of ferrite sheets and dielectric rods. The tunable property is originated from the ferromagnetic resonance and electric response of dielectric rods. The retrieved electromagnetic parameters and transmission characteristic showed that by simultaneously inspiring the ferromagnetic resonance and electric resonance, composite metamaterial can possess double-negative band in the resonant state. Moreover, this band was tunable by adjusting applied magnetic fields. The simulations and experiments verified that the composite metamaterial clearly displayed a tunable feature. The proposed method is simple in designing tunable metamaterials.
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