Physical Sciences and Mathematics Commons^™

Resonant Plasmonic–Biomolecular Chiral Interactions In The Far-Ultraviolet: Enantiomeric Discrimination Of Sub-10 Nm Amino Acid Films, Tiago Ramos Leite, Lin Zschiedrich, Orhan Kizilkaya, Kevin M. Mcpeak

Faculty Publications

Resonant plasmonic–molecular chiral interactions are a promising route to enhanced biosensing. However, biomolecular optical activity primarily exists in the far-ultraviolet regime, posing significant challenges for spectral overlap with current nano-optical platforms. We demonstrate experimentally and computationally the enhanced chiral sensing of a resonant plasmonic–biomolecular system operating in the far-UV. We develop a full-wave model of biomolecular films on Al gammadion arrays using experimentally derived chirality parameters. Our calculations show that detectable enhancements in the chiroptical signals from small amounts of biomolecules are possible only when tight spectral overlap exists between the plasmonic and biomolecular chiral responses. We support this conclusion …

Plasmonic Waveguides To Enhance Quantum Electrodynamic Phenomena At The Nanoscale, Ying Li, Christos Argyropoulos

Department of Electrical and Computer Engineering: Faculty Publications

The emerging field of plasmonics can lead to enhanced light-matter interactions at extremely nanoscale regions. Plasmonic (metallic) devices promise to efficiently control both classical and quantum properties of light. Plasmonic waveguides are usually used to excite confined electromagnetic modes at the nanoscale that can strongly interact with matter. The analysis of these nanowaveguides exhibits similarities with their low frequency microwave counterparts. In this article, we review ways to study plasmonic nanostructures coupled to quantum optical emitters from a classical electromagnetic perspective. These quantum emitters are mainly used to generate single-photon quantum light that can be employed as a quantum bit …

Interactions Of Organic Fluorophores With Plasmonic Surface Lattice Resonances, Robert J. Collison

Dissertations, Theses, and Capstone Projects

It is common knowledge that metals, alloys and pure elements alike, are lustrous and reflective, the more so when a metal surface is flat, polished, and free from oxidation and surface fouling. However, some metals reflect visible light, in the 380 nm to 740 nm range of wavelengths, much more strongly than others. In particular, some metals reflect wavelengths in certain portions of the ultraviolet (UV), visible, and near-infrared (NIR) regime, let us say 200 nm to 2000 nm, while absorbing light strongly in other segments of this range. There are several factors that account for this difference between various …

Electrodynamics Modeling Of Plasmonic-Organic Hybrid Waveguides, Marcus Michel

Pomona Senior Theses

Optical fibers have multiple advantages over conventional electrical connections, such as lower energy losses and higher bandwidth. To use optics for chip-to-chip communication, electro-optic (EO) modulators need to be scaled down to be incorporated on integrated circuits. This size reduction has been accomplished using plasmonic-organic hybrid (POH) waveguides, which make use of nonlinear organic EO materials and surface plasmon polaritons to achieve light modulation in devices with lengths on the micron scale. As these devices are just starting to be developed, there are many avenues for their potential optimization. In order to streamline and reduce the cost of the optimization …

Control Of Light-Matter Interactions Via Nanostructured Photonic Materials, Nicholas Proscia

Dissertations, Theses, and Capstone Projects

The thesis here investigates the manipulation of light-matter interactions via nanoscale engineering of material systems. When material systems are structured on the nanoscale, their optical responses can be dramatically altered. In this thesis, this is done in two primary ways: One method is by changing the geometry of nanostructures to induce a resonant behavior with incident electromagnetic field of optical wavelengths. This allows field enhancement in highly localized areas to strengthen exotic light-matter interactions that would otherwise be too weak to measure or for practical use. In this regard, the work presented here studies a voltage produced in a metal …

Grating Coupler For Surface Waves Based On Electrical Displacement Currents, Jonathan R. Brescia

Honors Undergraduate Theses

Bound electromagnetic surface waves can be excited by free-space waves on a corrugated conduction surface. These electromagnetic surface waves, called surface plasmon polaritons (SPPs), are coupled to a plasma of free charges, which travel together with the wave. We investigated the effect of separating metal corrugations from the smooth metal ground plane with a thin dielectric layer and show that SPPs can be excited via displacement currents. However, the SPP excitation resonances broaden and disappear as the dielectric thickness approaches 1% of the wavelength.

The Study Of Plasmonics In Nanohole Metallic Metamaterials, Kieffer J. Davieau

Electronic Thesis and Dissertation Repository

Plasmonics is the study of light-matter interaction. The interaction of incident light (photons) with surface plasmons present in metamaterials results in unique optical properties. Nanohole arrays are a metamaterial consisting of an array of sub-wavelength holes perforated in an optically thin metallic film which resides upon a dielectric material. The interaction of light with the surface plasmons present in the nanohole array leads to extraordinary optical transmission which produces resonance peaks with a higher intensity than the incident light. By changing the physical parameters of the nanohole array, such as hole size and periodicity, the resonance peaks can be tuned …

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 …

Omcvd Gold Nanoparticles Covalently Attached To Polystyrene For Biosensing Applications, Sivayini Kandeepan

Electronic Thesis and Dissertation Repository

Remarkable developments and successes were witnessed in the fabrication and implementation of optical sensors based on localized surface plasmon resonance (LSPR) for the investigation of chemical and biological material quantities and to detect lethal diseases such as cancer in early stages. Gold nanoparticles (AuNPs) are ideal candidate for sensing purposes due to their chemical stability, ease of surface functionalization and strong LSPR in the visible range. Although there are several designs of sensors published, most of them are still limited to small scale research laboratory use partly due to their high cost of fabrication and waste management, in particular critical …

The Study Of Nano-Optics In Hybrid Systems, Marek J. Brzozowski

Electronic Thesis and Dissertation Repository

In this thesis, we study the quantum light-matter interaction in polaritonic heterostructures. These systems are made by combining various nanocomponents, such as quantum dots, graphene films, metallic nanoparticles and metamaterials. These heterostructures are used to develop new optoelectronic devices due to the interaction between nanocomposites.

Photoluminescence quenching and absorption spectrum are determined and an explanatory theory is developed for these polaritonic heterostructures. Photoluminescence quenching is evaluated for a graphene, metallic nanoparticle and quantum dot system. It is shown that average distance between nanocomposites or concentration of nanocomposites affect the output these system produced. Photoluminescence quenching was also evaluated for a …

Transport And Optical Properties Of Low-Dimensional Complex Systems, Andrii Iurov

Dissertations, Theses, and Capstone Projects

Over the last five years of my research work, I, my research was mainly concerned with certain crucial tunneling, transport and optical properties of novel low-dimensional graphitic and carbon-based materials as well as topological insulators. Both single-electron and many-body problems were addressed. We investigated the Dirac electrons transmission through a potential barrier in the presence of circularly polarized light. An anomalous photon-assisted enhanced transmission is predicted and explained in a comparison with the well-known Klein paradox. It is demonstrated that the perfect transmission for nearly-head-on collision in an infinite graphene is suppressed in gapped dressed states of electrons, which is …

Novel Bimetallic Plasmonic Nanomaterials, Ritesh Sachan

Doctoral Dissertations

Plasmonic nanomaterials have attracted a lot of attention recently due to their application in various fields such as chemical and biological sensing, catalysis, energy harvesting and optical devices. However, there is a need to address several outstanding issues with these materials, including cost-effective synthesis, tunability in plasmonic characteristics, and long term stability. In this thesis, we have focused on bimetallic nanoparticles (NPs) of Ag and Co due to their immiscibility as well as their individual properties. First, a pulsed laser induced dewetting route was used to synthesize Ag-Co bimetallic plasmonic NPs. An synthesis parameter space was derived to show the …

Thermodynamic Limit To Photonic-Plasmonic Light-Trapping In Thin Films On Metals, Eric A. Schiff

Physics - All Scholarship

We calculate the maximum optical absorptance enhancements in thin semiconductor films on metals due to structures that diffuse light and couple it to surface plasmon polaritons. The calculations can be used to estimate plasmonic effects on light-trapping in solar cells. The calculations are based on the statistical distribution of energy in the electromagnetic modes of the structure, which include surface plasmon polariton modes at the metal interface as well as the trapped waveguide modes in the film. The enhancement has the form 4n²+nλ/h (n – film refractive index, λ – optical wavelength, h …

How Much Can Guided Modes Enhance Absorption In Thin Solar Cells?, Peter N. Saeta, Vivian E. Ferry, Domenico Pacifici, Jeremy N. Munday, Harry A. Atwater

All HMC Faculty Publications and Research

Absorption enhancement in thin metal-backed solar cells caused by dipole scatterers embedded in the absorbing layer is studied using a semi-analytical approach. The method accounts for changes in the radiation rate produced by layers above and below the dipole, and treats incoherently the subsequent scattering of light in guided modes from other dipoles. We find large absorption enhancements for strongly coupled dipoles, exceeding the ergodic limit in some configurations involving lossless dipoles. An antireflection-coated 100-nm layer of a-Si:H on Ag absorbs up to 87% of incident above-gap light. Thin layers of both strong and weak absorbers show similar strongly enhanced …