Electromagnetic Response and Broadband Utilities of Planar Metamaterials

Metamaterial (Smith, Pendry et al. 2004) interacts with electromagnetic waves in a resonant manner, affording us new giving rise to a new route for subwavelength photonic devices, such as compact antenna substrate (Li, Hang et al. 2005) and subwavelength resonant cavity (Zhou, Li et al. 2005; Li, Hao et al. 2006). Planar-type configuration,thanks to layer-by-layer fabrication technique, has been recognized as the most efficient and easiest way for the realization of metamaterials from microwave, terahertz, and optical regimes. And it is interesting to note that, in contrast to the common notion that the operational bandwidth of metamaterial is usually very narrow due to the local resonance nature, our recent studies show that planar metamaterial can be broadband in functionality (Wei, Cao et al. 2010; Wei, Cao et al. 2011).