Hyperbolic Metamaterial for Sub-diffraction Imaging at THz Frequencies

One of the main problems with the traditional imaging systems is that they can't support high spatial frequencies (i.e., high-k modes) evanescent waves, and thus results in classical diffraction limit. Metamaterials, especially, hyperbolic metamaterials can support high-k modes, and such modes are often wont to beat the diffraction limit. Here, we present an area 2D homogenized metamaterial slab as imaging device at THz frequencies. employing a simple analytical model and a transfer matrix method (TMM), we calculate transmission properties of slab. From the straightforward analytical model, we show that the metamaterial slab can resolve feature sizes below the diffraction limit. Our analytical model also confirms that transmission is unity at the Fabry-Perot resonances (FPRs), resulting in good image, and at off-FPRs, resonant enhancement of evanescent waves occurs at certain spatial frequencies, resulting in severe image distortion.