Metamaterials are sub-wavelength structures that designed for specific functionality. In metal-dielectric structures, plasmon mediation could be utilized for interesting physics and applied studies. Some of the issues we recently addressed are improving the light transmission efficiency, broadband, polarization and launch angle independent response of plasmonic structures in the linear and nonlinear optical domain. These have applications in light harvesting. Dielectric metamaterials are designed and demonstrated for truly broadband and omnidirectional antireflection coatings. In this talk, I will present some of our recent results.