Abstract
We demonstrate a two-handed metamaterial (THM), composed of highly symmetric three-layered structures operated at normal incidence. Not only does the THM exhibit two distinct allowed bands with righthanded and left-handed electromagnetic responses, but posses a further advantage of being independent to the polarizations of external excitations. In addition, the THM automatically matches the wave impedance in free space, leading to maximum transmittances about 0.8 dB in the left-handed band and almost 0 dB in the right-handed band, respectively. Such a THM can be employed for diverse electromagnetic devices including dual-band bandpass filters, ultra-wide bandpass filters and superlenses. © 2008 Optical Society of America.