Magnetically tunable double-negative material composed of ferrite-dielectric and metallic mesh

We designed and studied a magnetic tunable metamaterial composed of ferrite-dielectric and metallic mesh. The retrieved electromagnetic parameters and the transmission characteristic showed the composite has a double-negative regime in magnetized state. Moreover, this regime is tunable in external magnetic fields. The composite has a lower loss with minimum about -0.3 dB/mm. The simulations of the wave propagation on the interface of the composite clearly display a negative refraction. The negative indexes calculated from Snell's law are in good agreement with the indexes retrieved from S parameters, quantitatively confirms the negative index of the composite. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3359718]