Computational nanooptics in hyperbolic metamaterials and plasmonic structures

This dissertation concerns several problems in the fields of light interaction with nanostructured media, metamaterials, and plasmonics. We present a technique capable of extending operational bandwidth of hyperbolic metamaterials based on interleaved highly-doped InGaAs and undoped AlInAs multilayer stacks. The experimental results confirm theoretical predictions, exhibiting broadband negative refraction response in mid-infrared frequency.;We propose a new class of nanofocusing structures, named hypergrating, combining hyperbolic metamaterials with Fresnel optics, able to achieve extremely subwavelength focal spots (up to 50 times smaller than free-space wavelength) in the far field of the input interface. Several experimental realizations of hypergratings for visible and infrared frequencies are presented.;We further develop a new technique capable of imaging subwavelength objects with far-field measurements. The approach utilizes a diffraction grating, placed at the object plane, to convert subwavelength information of objects into propagating waves and project this information into far-field. The set of far-field measurements is used to deconvolute the images. The resolution of the proposed method can surpass 1/20-th of the free-space limit, strongly overperforming other subwavelength imaging technology.;We develop a new mode matching approach for analysis of scattering and propagation of surface and volume modes in multiple multilayered-stack structures. Our theory relies on the complete spectrum of free-space and guided electromagnetic modes to solve Maxwell's equations in the extended systems that have relatively few interfaces. We demonstrate the convergence of this technique on a number of plasmonic and metamaterial structures.;Finally, we consider the problem of plasmonic beam-steering structures consisting of a single slit flanked by a periodic set of metallic corrugations. We show that the light emitted by the structures forms a prolonged focal range that may extend for hundreds of wavelength from the plasmonic interface and eventually splits into two plasmonic beams. We develop a quantitative theory to physically describe the beam formations and evolution of field pattern.;The numerical and analytical results presented here can be applied to several nanooptics applications including deep-subwavelength imaging, nanolithography, on-chip communications, high-density energy focusing, and beaming devices, and can be used for metamaterial and plasmonic composites operating across ultraviolet, visible, infrared, or terahertz spectra.