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Full-Text Articles in Physics

Optimizing Switching Of Non-Linear Properties With Hyperbolic Metamaterials, James A. Ethridge, John G. Jones, Manuel R. Ferdinandus, Michael J. Havrilla, Michael A. Marciniak Nov 2022

Optimizing Switching Of Non-Linear Properties With Hyperbolic Metamaterials, James A. Ethridge, John G. Jones, Manuel R. Ferdinandus, Michael J. Havrilla, Michael A. Marciniak

Faculty Publications

Hyperbolic metamaterials have been demonstrated to have special potential in their linear response, but the extent of their non-linear response has not been extensively modeled or measured. In this work, novel non-linear behavior of an ITO/SiO2 layered hyperbolic metamaterial is modeled and experimentally confirmed, specifically a change in the sign of the non-linear absorption with intensity. This behavior is tunable and can be achieved with a simple one-dimensional layered design. Fabrication was performed with physical vapor deposition, and measurements were conducted using the Z-scan technique. Potential applications include tunable optical switches, optical limiters, and tunable components of laser sources.


Optical Signal Processing With Discrete-Space Metamaterials, Mohammad Moein Moeini Jan 2022

Optical Signal Processing With Discrete-Space Metamaterials, Mohammad Moein Moeini

Wayne State University Dissertations

As digital circuits are approaching the limits of Moore’s law, a great deal of efforthas been directed to alternative computing approaches. Among them, the old concept of optical signal processing (OSP) has attracted attention, revisited in the light of metamaterials and nano-photonics. This approach has been successful in realizing basic mathematical operations, such as derivatives and integrals, but it is difficult to be applied to more complex ones. Inspired by digital filters, we propose a radically new OSP approach, able to realize arbitrary mathematical operations over a nano-photonic platform. We demonstrate this concept for the case of spatial differentiation, image …


A Hybrid Achromatic Metalens, Fatih Balli, Mansoor A. Sultan, Sarah K. Lami, J. Todd Hastings Aug 2020

A Hybrid Achromatic Metalens, Fatih Balli, Mansoor A. Sultan, Sarah K. Lami, J. Todd Hastings

Electrical and Computer Engineering Faculty Publications

Metalenses, ultra-thin optical elements that focus light using subwavelength structures, have been the subject of a number of recent investigations. Compared to their refractive counterparts, metalenses offer reduced size and weight, and new functionality such as polarization control. However, metalenses that correct chromatic aberration also suffer from markedly reduced focusing efficiency. Here we introduce a Hybrid Achromatic Metalens (HAML) that overcomes this trade-off and offers improved focusing efficiency over a broad wavelength range from 1000-1800 nm. HAMLs can be designed by combining recursive ray-tracing and simulated phase libraries rather than computationally intensive global search algorithms. Moreover, HAMLs can be fabricated …


Experimental Testing Of A 3d-Printed Metamaterial Slow Wave Structure For High Power Microwave Generation, Antonio B. De Alleluia Nov 2019

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 …


3d Plasmonic Design Approach For Efficient Transmissive Huygens Metasurfaces, Bryan M. Adomanis, D. Bruce Burckel, Michael A. Marciniak Jul 2019

3d Plasmonic Design Approach For Efficient Transmissive Huygens Metasurfaces, Bryan M. Adomanis, D. Bruce Burckel, Michael A. Marciniak

Faculty Publications

In this paper we present a design concept for 3D plasmonic scatterers as high- efficiency transmissive metasurface (MS) building blocks. A genetic algorithm (GA) routine partitions the faces of the walls inside an open cavity into a M x N grid of voxels which can be either covered with metal or left bare, and optimizes the distribution of metal coverage needed to generate electric and magnetic modes of equal strength with a targeted phase delay (Φt) at the design wavelength. Even though the electric and magnetic modes can be more complicated than typical low order modes, with their spectral overlap …


Design, Fabrication, And Characterization Of Multilayer Hyperbolic Metamaterials, James Dilts May 2019

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 …


Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials, James A. Ethridge Mar 2019

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 …


Characterization Of Coupled Gold Nanoparticles In A Sparsely Populated Square Lattice, Roy Truett French Iii May 2017

Characterization Of Coupled Gold Nanoparticles In A Sparsely Populated Square Lattice, Roy Truett French Iii

Graduate Theses and Dissertations

Metal nanoparticles deposited in regular arrays spaced at optical wavelengths support a resonance due to a coherent coupling between localized surface plasmon mode and lattice diffraction allowing for engineering of tunable devices for use in biological sensors, nanoantennae, and enhanced spectroscopy. Techniques such as electron beam lithography, focused ion beam lithography, nanosphere lithography, and nanoimprint lithography are used for fabrication but are limited by cost, device throughput, and small deposition. Polymer soft lithography and continuous dewetting of particles is a potentially viable alternative showing promise in all of those areas. This thesis developed the fabrication of a refined hydrophilic nanoimprinted …


Interference Of Light In Multilayer Metasurfaces: Perfect Absorber And Antireflection Coating, Khagendra Prasad Bhattarai Apr 2017

Interference Of Light In Multilayer Metasurfaces: Perfect Absorber And Antireflection Coating, Khagendra Prasad Bhattarai

USF Tampa Graduate Theses and Dissertations

We have studied several metamaterials structures with multiple layers by explaining them theoretically and verifying experimentally. The engineered structures we have designed work either as a perfect absorber or antireflection coating. The multilayer model as we call it Three Layer Model (TLM) has been developed, which gives the total reflection and transmission as a function of reflection and transmission of individual layers. By manipulating the amplitude and phase of the reflection and the transmission of the individual layers, we can get the required functionality of the optoelectronic devices. To get zero reflection in the both perfect absorber and the antireflection …


Photonicstd-2d: Modeling Light Scattering In Periodic Multilayer Photonic Structures, Alexey Bondarev, Shaimaa Azzam, Zhaxylyk Kudyshev, Alexander V. Kildishev Aug 2016

Photonicstd-2d: Modeling Light Scattering In Periodic Multilayer Photonic Structures, Alexey Bondarev, Shaimaa Azzam, Zhaxylyk Kudyshev, Alexander V. Kildishev

The Summer Undergraduate Research Fellowship (SURF) Symposium

Efficient modeling of electromagnetic processes in optical and plasmonic metamaterials is important for enabling new and exciting ways to manipulate light for advanced applications. In this work, we put together a tool for numerical simulation of propagation of normally incident light through a nanostructured multilayer composite material. The user builds a unit cell of a given material layer-by-layer starting from a substrate up to a superstrate, splitting each layer further into segments. The segments are defined by width and material -- dielectric, metal or active medium. Simulations are performed with the finite difference time domain (FDTD) method. A database of …


Nanophotonics For Dark Materials, Filters, And Optical Magnetism, Mengren Man Aug 2016

Nanophotonics For Dark Materials, Filters, And Optical Magnetism, Mengren Man

Open Access Dissertations

Research on nanophotonic structures for three application areas is described, a near perfect optical absorber based on a graphene/dielectric stack, an ultraviolet bandpass filter formed with an aluminum/dielectric stack, and structures exhibiting homogenizable magnetic properties at infrared frequencies. The graphene stack can be treated as a effective, homogenized medium that can be designed to reflect little light and absorb an astoundingly high amount per unit thickness, making it an ideal dark material and providing a new avenue for photonic devices based on two-dimensional materials. Another material stack arrangement with thin layers of metal and insulator forms a multi-cavity filter that …


Intensity Control Of Dielectric Barrier Discharge Filaments, Matthew Crawford Paliwoda Jan 2016

Intensity Control Of Dielectric Barrier Discharge Filaments, Matthew Crawford Paliwoda

Masters Theses

"When operated in a filamentary mode, a volume dielectric barrier discharge (DBD) is known to produce patterned plasma structures. These structures are currently being explored for reconfigurable metamaterial applications. In this work the presence and intensity of a single filament, within an array of filaments, was controlled by adjusting the voltage to that filament's individual needle electrode. The current, voltage, and time-averaged normalized light intensity were measured while varying the voltage of the needle through a self-biasing resistance. For a 7.5 kV, 3.2 kHz DBD in air, the needle-controlled filament intensity varies from that of the surrounding filaments to zero …


Plasmonics On The Slope Of Enlightenment: The Role Of Transition Metal Nitrides, U. Guler, A. Kildishev, A. Boltasseva, V. Shalaev Jan 2015

Plasmonics On The Slope Of Enlightenment: The Role Of Transition Metal Nitrides, U. Guler, A. Kildishev, A. Boltasseva, V. Shalaev

U. Guler

The key problem currently faced by plasmonics is related to material limitations. After almost two decades of extreme excitement and research largely based on the use of noble metals, scientists have come to a consensus on the importance of exploring alternative plasmonic materials to address application-specific challenges to enable the development of new functional devices. Such a change in motivation will undoubtedly lead to significant advancements in plasmonics technology transfer and could have a revolutionary impact on nanophotonic technologies in general. Here, we report on one of the approaches that, together with other new material platforms, mark an insightful technology-driven …


Control Of Light-Matter Interaction Via Dispersion Engineering, Harish Natarajan Swaha Krishnamoorthy Oct 2014

Control Of Light-Matter Interaction Via Dispersion Engineering, Harish Natarajan Swaha Krishnamoorthy

Dissertations, Theses, and Capstone Projects

This thesis describes the design, fabrication and characterization of certain nanostructures to engineer light-matter interaction. These materials have peculiar dispersion properties owing to their structural design, which is exploited to control spontaneous emission properties of emitters such as quantum dots and dye molecules. We will discuss two classes of materials based on the size of their unit cell compared to the wavelength of the electromagnetic radiation they interact with. The first class are hyperbolic metamaterials (HMM) composed of alternate layers of a metal and a dielectric of thicknesses much smaller than the wave- length. Using a HMM composed of silver …


Quantum Levitation Using Metamaterials, Venkatesh K. Pappakrishnan Jul 2014

Quantum Levitation Using Metamaterials, Venkatesh K. Pappakrishnan

Doctoral Dissertations

The emergence of an attractive vacuum force (Casimir force) between two purely dielectric materials can lead to an increase in the friction and the stiction effects in nanoscale devices, resulting in degradation or decreased performance. Thus, it is of high practical importance that the conditions for the reversal of the Casimir force from attractive to repulsive are identified. Although the repulsive Casimir force has been considered for high dielectric materials as an intermediate (between the plates) medium, so far no realistic system has been proposed that can demonstrate quantum levitation with air/vacuum as a host medium. Since air is the …


Large Area Conformal Infrared Frequency Selective Surfaces, Jeffrey D'Archangel Jan 2014

Large Area Conformal Infrared Frequency Selective Surfaces, Jeffrey D'Archangel

Electronic Theses and Dissertations

Frequency selective surfaces (FSS) were originally developed for electromagnetic filtering applications at microwave frequencies. Electron-beam lithography has enabled the extension of FSS to infrared frequencies; however, these techniques create sample sizes that are seldom appropriate for real world applications due to the size and rigidity of the substrate. A new method of fabricating large area conformal infrared FSS is introduced, which involves releasing miniature FSS arrays from a substrate for implementation in a coating. A selective etching process is proposed and executed to create FSS particles from crossed-dipole and square-loop FSS arrays. When the fill-factor of the particles in the …


Digitally Manufactured Spatially Variant Photonic Crystals, Javier Jair Pazos Jan 2014

Digitally Manufactured Spatially Variant Photonic Crystals, Javier Jair Pazos

Open Access Theses & Dissertations

Metamaterials and photonic crystals are engineered composites that exhibit electromagnetic properties superior to those found in nature. They have been shown to produce novel and useful phenomena that allow extraordinary control over the electromagnetic field. One of these phenomena is self-collimation, an effect observed in photonic crystals in which a beam of light propagates without diffraction and is forced to flow in the direction of the crystal. Self-collimation however, like many of the mechanisms enabled through dispersion engineering, is effective in directions only along the principal axes of the lattice. To this effect, a general purpose synThesis procedure was developed …


Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar Oct 2012

Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar

Srinivas Sridhar

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal surface plasmon modes. A quantitative model based on effective medium theory is in excellent agreement with experimental data, and points to specific composite configurations and wavelength regimes where such structures can have applications as negative refraction media for imaging.


Super-Resolution Imaging Using A Three-Dimensional Metamaterials Nanolens, B. Casse, W. Lu, Y. Huang, E. Gultepe, L. Menon, S. Sridhar Oct 2012

Super-Resolution Imaging Using A Three-Dimensional Metamaterials Nanolens, B. Casse, W. Lu, Y. Huang, E. Gultepe, L. Menon, S. Sridhar

Srinivas Sridhar

Super-resolution imaging beyond Abbe's diffraction limit can be achieved by utilizing an optical medium or "metamaterial" that can either amplify or transport the decaying near-field evanescent waves that carry subwavelength features of objects. Earlier approaches at optical frequencies mostly utilized the amplification of evanescent waves in thin metallic films or metal-dielectric multilayers, but were restricted to very small thicknesses (⪡λ, wavelength) and accordingly short object-image distances, due to losses in the material. Here, we present an experimental demonstration of super-resolution imaging by a low-loss three-dimensional metamaterial nanolens consisting of aligned gold nanowires embedded in a porous alumina matrix. This composite …


Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar Oct 2012

Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar

Donald Heiman

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal surface plasmon modes. A quantitative model based on effective medium theory is in excellent agreement with experimental data, and points to specific composite configurations and wavelength regimes where such structures can have applications as negative refraction media for imaging.


Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar Oct 2012

Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar

Latika Menon

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal surface plasmon modes. A quantitative model based on effective medium theory is in excellent agreement with experimental data, and points to specific composite configurations and wavelength regimes where such structures can have applications as negative refraction media for imaging.


Super-Resolution Imaging Using A Three-Dimensional Metamaterials Nanolens, B. D. F. Casse, W. T. Lu, Y. J. Huang, E. Gultepe, L. Menon, S. Sridhar Oct 2012

Super-Resolution Imaging Using A Three-Dimensional Metamaterials Nanolens, B. D. F. Casse, W. T. Lu, Y. J. Huang, E. Gultepe, L. Menon, S. Sridhar

Latika Menon

Super-resolution imaging beyond Abbe's diffraction limit can be achieved by utilizing an optical medium or "metamaterial" that can either amplify or transport the decaying near-field evanescent waves that carry subwavelength features of objects. Earlier approaches at optical frequencies mostly utilized the amplification of evanescent waves in thin metallic films or metal-dielectric multilayers, but were restricted to very small thicknesses (⪡λ, wavelength) and accordingly short object-image distances, due to losses in the material. Here, we present an experimental demonstration of super-resolution imaging by a low-loss three-dimensional metamaterial nanolens consisting of aligned gold nanowires embedded in a porous alumina matrix. This composite …