Colossal optical activity of split-ring resonator arrays for millimeter waves

Abstract

We have studied the optical activity of bilayered split-ring resonator arrays for millimeter waves. Using quasi-optical technique within controlled polarization rotation we were able to measure transmission and phase shift of these arrays within geometries with parallel and crossed polarizers. We determined experimentally the complex 2×2 transmission matrix which fully characterizes the arrays. We obtain an optical rotation of up to 600 deg/λ for the array thickness of 90 μm and at 3 mm wavelength. The polarization dependence of the optical activity can be effectively suppressed by introducing higher symmetries in the structures. Our results demonstrate the possibility to effectively control and investigate the polarization state of millimeter wave radiation. © 2010 American Institute of Physics.