Optical Properties of Amorphous Nanolayers
Optical Properties of Amorphous Nanolayers
Wednesday, April 6, 2011 at 4:00 pm
Weniger 304
Nicholas Kuhta
Metamaterials are structures which contain features that are much smaller than the wavelength of light, and have physical properties which are caused by geometry instead of constituent material response. In our latest collaboration we have developed a new metamaterial platform based on materials with amorphous morphology. We use DC Magnetron Sputtering and Solution Spin Coating techniques to fabricate atomically smooth planar amorphous metal-dielectric nanolayers. The resulting composites display effective medium characteristics with elliptical and hyperbolic anisotropic dispersion. Varying the chemical composition and metal-dielectric ratios in these films enables the possibility of engineering dispersion to tailored applications. Although they are much less conductive than noble metals, amorphous metals are the leading candidate for fabricating the thinnest possible completely continuous metal. During this talk I will show results from our layered amorphous metal – dielectric structures, and discuss the physics behind this system. Effective medium theory, anisotropic dispersion engineering, and negative refraction will be discussed in detail.