Reflection and negative refraction of left-handed metamaterials at microwave frequencies

We experimentally investigated the microwave reflection of the negative permeability material composed of periodical arrays of the copper split-ring resonators (SRRs).The negative dielectric materials are composed of periodical arrays of copper wires and left-handed materials(LHMs) in a planar slab waveguide, and the microwave is incident to the surface in different directions.We also investigated the negative refraction through a prism fabricated from the LHMs.The experimental results show that for the negative permeability materials,there is a reflection peak at the resonance frequencies of the SRRs, and the reflectivity of the negative dielectric material is closed to 0dB.A single smaller reflection peak occurs in the reflected curve of the LHMs,the reflectivity of which increases with the incident direction,that is,the reflection increases.The reflection peak has a shift with respect to the transmission peak. It is demonstrated that negative refractive index of -0.796 occurs in the LHMs at the frequency o 800MHz.