Nano-scale Metamaterials: Fabrication and Optical Measurements from THz towards visible

We have designed, fabricated, and optically measured several different nano-scale metamaterials. We employ e-beam nano-lithography technology at LBNL's CXRO for fabricating these structures on extremely thin SiN substrates so that they are close to free-standing. Optical properties were measured as a function of incidence angle and polarization using the ALS synchrotron IR beamlines. We directly observe strong magnetic resonances consistent with negative magnetic permeability in our samples at THz through near-IR optical frequencies. We will compare the results to detailed simulations. Finally, we will report on our progress towards constructing a negative index of refraction nano-scale metamaterial.