Tunable two-dimensional left-handed material consisting of ferrite rods and metallic wires

We demonstrate a magnetically tunable and two-dimensional (2D) left-handed material (LHM) consisting of an array of ferrite rods and metallic wires by experiments and simulations. It shows that the ferrite rod has a 2D isotropic negative permeability. By combining the ferrite rods with metallic wires, we observe experimentally a 2D LH passband that can be tuned dynamically, continuously and reversibly by an external magnetic field within in a wide frequency range with a response of 3.5 GHz/kOe. Retrieved effective parameters based on simulated scattering parameters show that operating frequency and value of negative refraction index can be conveniently tuned by changing the external magnetic field.