A5058707475- Plasmonic and Surface Plasmon Research
- Metamaterials and Metasurfaces Applications
- Photonic Crystals and Applications
- Magnetism in coordination complexes
- Advanced Antenna and Metasurface Technologies
- Photonic and Optical Devices
- Crystallization and Solubility Studies
- Orbital Angular Momentum in Optics
- X-ray Diffraction in Crystallography
- Silicone and Siloxane Chemistry
- Space Satellite Systems and Control
- Optical Coatings and Gratings
- Gold and Silver Nanoparticles Synthesis and Applications
- Mechanical and Optical Resonators
- Heusler alloys: electronic and magnetic properties
- Metal-Organic Frameworks: Synthesis and Applications
- Advanced Fiber Laser Technologies
- Astro and Planetary Science
- Organic and Molecular Conductors Research
- Thermal Radiation and Cooling Technologies
- Infrared Target Detection Methodologies
- Crystal Structures and Properties
- MXene and MAX Phase Materials
- Inorganic Fluorides and Related Compounds
- TiO2 Photocatalysis and Solar Cells
University of Hartford
2016-2024
University of Massachusetts Lowell
2012-2021
University of Northern Colorado
2016
University of Massachusetts Amherst
2014
Clark University
2004-2009
Auburn University
2006-2007
Livingstone Hospital
1963
University of Cape Town
1963
We present an analytical description of the nonlocal optical response plasmonic nanowire metamaterials that enable negative refraction, subwavelength light manipulation, and emission lifetime engineering. show dispersion waves propagating in media results from coupling transverse longitudinal electromagnetic modes supported by composite derive effective medium approximation for this dispersion. profiles electric field across unit cell, use these expressions to solve long-standing problem...
Light-matter interactions can be strongly modified by the surrounding environment. Here, we report on first experimental observation of molecular spontaneous emission inside a highly non-local metamaterial based plasmonic nanorod assembly. We show that process is dominated not only topology its local effective medium dispersion, but also response composite, so metamaterials with different geometric parameters same properties exhibit Purcell factors. A record-high enhancement decay rate...
Nanowire-based plasmonic metamaterials exhibit many intriguing properties related to the hyperbolic dispersion, negative refraction, epsilon-near-zero behavior, strong Purcell effect, and nonlinearities. We have experimentally numerically studied electromagnetic modes of individual nanowires (meta-atoms) forming metamaterial. High-resolution, scattering-type near-field optical microscopy has been used visualize intensity phase modes. Numerical analytical modeling mode structure is in...
Light–matter interactions at a particular point in material may be dominated by properties of the medium this point, or they could affected electromagnetic surrounding regions. In former case, is said to local, while latter, it nonlocal. Recent studies light–matter composite optical metamaterials showed that nonlocal effects enable new phenomena are not acounted for conventional, local effective description. Up until now majority focused on with spatially uniform parameters. However,...
The hyperbolic and plasmonic properties of silicon nanowire/Ag arrays have been investigated. aligned nanowire were formed coated by atomic layer deposition Ag, which itself is a metamaterial due to its unique mosaic film structure. theoretical numerical studies suggest that the fabricated dispersion in visible IR ranges spectrum. predictions indirectly confirmed polarized reflection spectra, showing reduction p polarization comparison s polarization. Studies dye emission on top Si/Ag show...
Abstract Water to cement (w/c) ratio is usually the most important parameter specified in concrete design and sometimes subject of dispute when a shortfall strength or durability an issue. However, determination w/c hardened by testing very difficult once has set. This paper presents results from inter-laboratory round-robin study organised Applied Petrography Group evaluate compare microscopy methods for measuring concrete. Five prisms with ratios ranging 0.35 0.55, but otherwise identical...
Hot carrier dynamics in plasmonic nanorod metamaterials and its influence on the metamaterial's optical Kerr nonlinearity is studied. The electron temperature distribution induced by an pump metallic component of metamaterial leads to geometry‐dependent variations response as observed both transmission reflection properties slab. Thus, ultrafast a can be controlled via modal engineering. Both transient relaxation time magnitude are shown depend modal‐induced spatial profile hot‐electron...
An unprecedented antiferromagnetic exchange of -234 K in Cu(2,5-dimethylpyrazine)Br(2) is shown experimentally and theoretically to propagate via through-space interactions between Br ions rather than through-bond interactions.
Nonlinear processes are at the core of many optical technologies whose further development require optimized materials suitable for nanoscale integration.Here we demonstrate emergence a strong bulk second-order nonlinear response in plasmonic nanorod composite comprised centrosymmetric materials.We develop an effective-medium description underlying physics, compare its predictions to experimental results, and analyze limits applicability.We tunable generation p-polarized second-harmonic...
We present analytical and computational studies of light emission in nonlocal metamaterials formed by arrays aligned plasmonic nanowires. demonstrate that the lifetime these composites is a complex function geometrical material parameters system cannot be reduced to "trivial" hyperbolic or elliptical dispersion topology homogenised metamaterial. In particular, our suggest Purcell factor can often maximized when composite operates elliptic regime, with strong radiation coupling an additional...
We demonstrate that the incorporation of nonlocal nanowire metamaterials into Salisbury screens allows for a substantial reduction dependence incident angle on absorption maximum. Realizations angle-independent near-IR, mid-IR, and GHz frequencies are proposed their performances analyzed analytically numerically. It is shown effective medium theory adequately describes angular nanowire-based screens.
A new tetracopper(II) coordination compound, [Cu4Cl6O(iQuin)4] (1, iQuin = isoquinoline), with an adamantane-like structure is reported. The compound crystallizes in the tetragonal space group P4/n one crystallographically unique Cu(II) and oxide ions, two chloride ions. Variable temperature magnetic measurements reveal dominant antiferromagnetic interactions, but crystal suggests likelihood of frustration compound. Modeling results indicate presence competing Jap/kB=−61.1(7) K...
We demonstrate, experimentally and theoretically, a new class of angle-insensitive band-pass optical filters that utilize anisotropy plasmonic nanorod metamaterials, in both ε ≃ −1 epsilon-near-infinity regimes, to minimize dependence path on the incident angle. The operating wavelength bandwidth filter can be engineered by controlling geometry metamaterial. Experimental results are agreement with full wave numerical analytical solutions Maxwell's equations. Theoretical simulations show...
We present an analytical approach that adequately describes the nonlocal optical response for plasmonic nanowire metamaterials. The technique provides insight into origin of additional wave and allows implementation boundary conditions.
Presently, solar cells are covered with Ce-doped microsheet cover glasses that attached Dow Corning DC 93500 silicone adhesive. This general approach has been used from the beginning of space exploration, however, it is expensive and time consuming. Furthermore, as voltage arrays increases, significant arcing occurred in arrays, leading to loss satellite power. problem could be ameliorated if glass extended over edges cell, but this would impact packing density. An alternative idea might...
We present numerical and analytical studies of the nonlocal optical response for plasmonic nanorod metamaterials. Dispersion photonic modes has been studied an description effective permittivity developed.
We present a new, to the best of our knowledge, formalism in design metasurface beamsplitters with arbitrarily chosen split beam directions. This technique is based on well-established array theory; particular Fourier transform method synthesis, cast an obliquely incident plane wave multiple designer-selected scattering To show efficacy this approach, beamsplitting reflector designed and verified experimentally numerically. The fabricated by screen-printing patterns metallic...
We present a sensor that utilizes modified single-frequency split beam metasurface reflector to measure the refractive index of materials ranging from one three. Samples are placed into cavity between PCB-etched dielectric and reflecting ground plane. It is illuminated using 10.525 GHz free-space transmit horn with angles measured by sweeping receiving around setup. Predetermined changes in determined through simulations will coincide material's index. The designed Fourier transform method...
We demonstrate excitation of additional electromagnetic waves in plasmonic nanorod metamaterials. These arising from a nonlocal optical response metamaterial results strongly enhanced ultrafast nonlinear response.