Towards 3D Electromagnetic Metamaterials in the THz Range

SSLS has been using its lithography-based rmicro/nanofabrication facility LiMiNT (Lithography for Micro and Nanotechnology) and its infrared spectro/microscopy facility ISMI to develop and characterize the first electromagnetic metamatenials having their spectral response in the THz range. Derived from Pendry's nested-split-ring resonator design, these structures require micro/nanofabrication in order to have resonances in the THz range. They exhibit a negative refractive index and hold promise of sub-diffraction limit imaging. Besides the reduction of the size of the resonating structures to extend the spectral range towards the visible, outstanding issues include the production of high -aspect-ratio resonators that are sensitive for the magnetic field in any direction (3D sensitivity) and the capability to produce copious amounts of the electromagnetic metamaterials with a good yield. In this paper, we shall report on first results of 3D EM3 structures made by inclined exposures.