Free-standing THz electromagnetic metamaterials

Abstract

Using micromanufactured S-shaped gold strings suspended in free space by means of window-frames, we experimentally demonstrate an electromagnetic meta-material (EM3) in which the metallic structures are no longer embedded in matrices or deposited on substrates such that the response is solely determined by the geometrical parameters and the properties of the metal. Two carefully aligned and assembled window-frames form a bi-layer chip that exhibits 2D left-handed pass-bands corresponding to two different magnetic resonant loops in the range of 1.4 to 2.2 THz as characterized by Fourier transform, interferometry and numerical simulation. Chips have a comparably large useful area of 56 mm2. Our results are a step towards providing EM 3 that fulfill the common notions of a material. © 2008 Optical Society of America.