No description available.

A pair of light beams that have orthogonal polarizations and equal intensity can be generated through reflection and refraction of a monochromatic light at a dielectric surface. Sytematic procedures to design beam splitters which can produce such output light beams are described in this thesis. Two designs that are of particular interest are prismatic substrates coated by a single layer and a double layer of thin films. Specific examples of each beam splitter in the visible and infrared are included. The performance of each beam splitter as a function of incidence angle, film thickness, and wavelength is also discussed.

Thesis advisor: Krzysztof Kempa / Thesis advisor: Zhifeng Ren / In the past few decades, accompanied by the fascinating development of micro- and nano-fabrication techniques, the successful integration of subwavelength optics and multilayer structures has led to a number of remarkable discoveries. In this work, I present both experimental and theoretical investigations of the optics of thin metallic films with micro-/nano-scale perforations in the UV-VIS-IR ranges. Different fabrication techniques are employed, including nanosphere lithography, grain boundary lithography, crack templates, and sintered nanoparticles. The optical properties these films are studied, revealing important relation between optical response and the film geometry. This includes the evolution of plasmonic resonances in a series of periodic arrays of holes in a metallic film, with hole sizes increasing gradually until an array of islands is achieved. This evolution is an analog of the percolation problem, and critical phenomena are observed at the percolation threshold. Multilayer broad-band electromagnetic absorbers are also designed and fabricated based on the study of these perforated films. Parallel with these observations, an analytical coherence model is proposed to bridge the subwavelength and superwavelength limits. Such a model also provides an alternative way to handle thin random structures, avoiding large quantity of numerical computation. These studies can find applications in the design of sensors, ultrathin solar cells and transparent electrodes, as well as in applications where random structures are widely used. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

No description available.

This thesis is about the multicolored gradients seen when using certain dichroic color lters with artificial light. As of now, this phenomenon lacks a unambiguous descriptor, and “Goniochromatic Gradient” is proposed. With help of optical physics, the science of color vision and information about dichroic products, principles for the relationship between goniochromatic gradients and dichroic filters are formulated for anyone interested in exploring this visual phenomenon.