Dual-band negative index metamaterial: double negative at 813nm and single negative at 772nm

Uday K. Chettiar, Purdue University
Alexander V. Kildishev, Birck Nanotechnology Center, Purdue University
Hsiao-Kuan Yuan, Purdue University - Main Campus
Wenshan Cai, Purdue University - Main Campus
Shumin Xiao, Purdue University
V. P. Drachev, Birck Nanotechnology Center, School of Electrical and Computer Engineering, Purdue University
V. M. Shalaev, Birck Nanotechnology Center and School of Electrical and Computer Engineering, Purdue University

Abstract

This work is concerned with the experimental demonstration of a dual-band negative index metamaterial. The sample is double negative (showing both a negative effective permeability and a negative effective permittivity) for linearly polarized light with a wavelength between 799 and 818 nm, and the real part of its refractive index is approximately - 1.0 at 813 nm. The ratio of -Re(n) /Im(n) is close to 1.3 at 813 nm. For an orthogonal polarization, the same sample also exhibits a negative refractive index in the visible (at 772 nm). The spectroscopic measurements of the material are in good agreement with the results obtained from a finite-element electromagnetic solver for the actual geometry of the fabricated sample at both polarizations.