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Full-Text Articles in Engineering
Experimental Testing Of A 3d-Printed Metamaterial Slow Wave Structure For High Power Microwave Generation, Antonio B. De Alleluia
Experimental Testing Of A 3d-Printed Metamaterial Slow Wave Structure For High Power Microwave Generation, Antonio B. De Alleluia
Electrical and Computer Engineering ETDs
A metamaterial (MTM) high power microwave (HPM) vacuum electron device (VED) was developed using 3D printing technology. The specific geometric pattern of the source can produce both negative permittivity and permeability to interact with a relativistic electron beam. The electron beam is generated using a pulsed electron accelerator with a maximum energy of 700 keV and lasting approximately 16 ns. The design of this novel VED consists of a circular waveguide loaded with complementary split-ring resonators in a linear periodic arrangement in which the relativistic beam travels guided by a magnetic field. The electrons interact with the MTM producing electromagnetic …
Airborne Topological Acoustics, Xingxing Liu
Airborne Topological Acoustics, Xingxing Liu
Electronic Thesis and Dissertation Repository
Advances in topological acoustics are leading to potential development for noise attenuation, ultrasonic imaging, sound manipulation, and information delivering, etc. Recently, ideas and methodologies from condensed-matter physics, such as the quantum Hall effect (QHE), the quantum spin Hall effect (QSHE), and the quantum valley Hall effect (QVHE), combined with configurations of sonic crystals and metamaterials, have been investigated in manipulating acoustic transmissions in the form of one-way edge modes and defect-immune protected acoustics. However, many related studies are still in their infancy and mostly rely on bulky, noisy, overly complicated, untunable and narrow-band-effective facilities, and so it is highly desirable …
Design, Fabrication, And Characterization Of Multilayer Hyperbolic Metamaterials, James Dilts
Design, Fabrication, And Characterization Of Multilayer Hyperbolic Metamaterials, James Dilts
Graduate Theses - Physics and Optical Engineering
Hyperbolic metamaterials (HMMs) show extreme anisotropy, acting as metals and dielectrics along orthogonal directions. They are designed using the effective medium theory (EMT) and can be fabricated using standard semiconductor processing techniques. Current techniques used to characterize the optical behavior of HMMs have a high complexity or are unable to robustly determine the complex permittivity tensor. We describe the details of a procedure to obtain a very low mean-squared-error (MSE) for extraction of permittivity from hyperbolic metamaterials using spectroscopic ellipsometry. We have verified our procedure by fabricating three different samples of various materials and fill factors designed to have a …
Strong Light Matter Interactions At The Nanoscale: Formation Of Polaritons In Hybrid Dielectric Metasurfaces, Huck Kootenai Green
Strong Light Matter Interactions At The Nanoscale: Formation Of Polaritons In Hybrid Dielectric Metasurfaces, Huck Kootenai Green
Electrical and Computer Engineering ETDs
Study and control of light matter interactions at the nanoscale is an extremely active topic of research as it can create intriguing new opportunities for sensing, optoelectronics, nonlinear optics, and other nanophotonic devices. Various platforms have been investigated to study light-matter interactions at the nanoscale. The most recent explorations in research come from one platform, metasurfaces – planar equivalents of three dimensional metamaterials. Previous studies of strong light matter interaction have been demonstrated on metallic metasurfaces. However, there are little experiments demonstrating strong light-matter interaction in all dielectric metasurfaces. We present a study demonstrating strong light-matter interactions in a hybrid …
Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials, James A. Ethridge
Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials, James A. Ethridge
Theses and Dissertations
The future of optical devices involves manipulation of nanoscale structure in order to achieve full control over the properties of the device. In fields as diverse as directed energy, remote sensing, optical communications and optical computing, these devices promise to greatly improve performance and efficiency. To advance this further, novel samples that incorporate both photonic crystal (PhC) structure and metamaterial properties, known as PhC metamaterials, are proposed. These PhC metamaterials allow for complete control over the directionality of the light-matter interaction to serve in these new applications. To develop this technology, first, metamaterials with no PhC structure are fabricated using …
Enhancing The Resolution Of Imaging Systems By Spatial Spectrum Manipulation, Wyatt Adams
Enhancing The Resolution Of Imaging Systems By Spatial Spectrum Manipulation, Wyatt Adams
Dissertations, Master's Theses and Master's Reports
Much research effort has been spent in the 21st century on superresolution imaging techniques, methods which can beat the diffraction limit. Subwavelength composite structures called ``metamaterials" had initially shown great promise in superresolution imaging applications in the early 2000s, owing to their potential for nearly arbitrary capabilities in controlling light. However, for optical frequencies they are often plagued by absorption and scattering losses which can decay or destroy their interesting properties. Similar issues limit the application of other superresolution devices operating as effective media, or metal films that can transfer waves with large momentum by supporting surface plasmon polaritons. In …