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Plasmon-Enhanced Quadrupolar Transitions With Nanostructured Graphene, Stephen Sanders
Plasmon-Enhanced Quadrupolar Transitions With Nanostructured Graphene, Stephen Sanders
Shared Knowledge Conference
Many important molecules have quadrupolar excitations which occur at much slower rates than the competing dipolar transitions and hence are termed forbidden. In this work, we propose a new approach to enhance quadrupolar transitions using graphene nanostructures. We provide a detailed investigation of the enhanced transition rate in the vicinity of graphene nanoislands and use rigorous computational methods to analyze how this quantity changes with the geometrical and material parameters of the nanoisland. To support these calculations we also provide a semi-analytic approach. Finally, we investigate the performance of arrays of graphene nanoribbons, which constitutes a suitable platform for the …
Genetic Algorithm Design Of Photonic Crystals For Energy-Efficient Ultrafast Laser Transmitters, Troy A. Hutchins-Delgado
Genetic Algorithm Design Of Photonic Crystals For Energy-Efficient Ultrafast Laser Transmitters, Troy A. Hutchins-Delgado
Shared Knowledge Conference
Photonic crystals allow light to be controlled and manipulated such that novel photonic devices can be created. We are interested in using photonic crystals to increase the energy efficiency of our semiconductor whistle-geometry ring lasers. A photonic crystal will enable us to reduce the ring size, while maintaining confinement, thereby reducing its operating power. Photonic crystals can also exhibit slow light that will increase the interaction with the material. This will increase the gain, and therefore, lower the threshold for lasing to occur. Designing a photonic crystal for a particular application can be a challenge due to its number of …
Nonthermal Dark Matter From Early Matter Domination, Jacek Ksawery Osinski
Nonthermal Dark Matter From Early Matter Domination, Jacek Ksawery Osinski
Shared Knowledge Conference
Dark matter (DM) production in the early universe traditionally assumes a standard thermal history where the universe is in a radiation-dominated phase after the end of inflation until matter-radiation equality. However, the presence of additional scalar fields (which is a generic prediction of explicit string constructions) can lead to an epoch of early matter domination (EMD) that ends before the onset of big bang nucleosynthesis. Such an EMD phase has important cosmological consequences and renders thermal production of DM irrelevant. We present three scenarios for DM production involving an era of EMD: evaporation of primordial black holes into DM, DM …
Combined High-Speed Single Particle Tracking Of Membrane Proteins And Super-Resolution Of Membrane-Associated Structures, Hanieh Mazloom Farsibaf, Keith A. Lidke
Combined High-Speed Single Particle Tracking Of Membrane Proteins And Super-Resolution Of Membrane-Associated Structures, Hanieh Mazloom Farsibaf, Keith A. Lidke
Shared Knowledge Conference
Many experiments have shown that the diffusive motion of lipids and membrane proteins are slower on the cell surface than those in artificial lipid bilayers or blebs. One hypothesis that may partially explain this mystery is the effect of the cytoskeleton structures on the protein dynamics. A model proposed by Kusumi [1] is the Fence-Picket Model which describes the cell membrane as a set of compartment regions, each ~ 10 to 200 nm in size, created by direct or indirect interaction of lipids and proteins with actin filaments just below the membrane. To test this hypothesis, we have assembled a …
Sampling Complexity Of Bosonic Random Walkers On A One-Dimensional Lattice, Gopikrishnan Muraleedharan, Akimasa Miyake, Ivan Deutsch
Sampling Complexity Of Bosonic Random Walkers On A One-Dimensional Lattice, Gopikrishnan Muraleedharan, Akimasa Miyake, Ivan Deutsch
Shared Knowledge Conference
Computers based quantum logic are believed to solve problems faster and more efficiently than computers based on classical boolean logic. However, a large-scale universal quantum computer with error correction may not be realized in near future. But we can ask the question: can we devise a specific problem that a quantum device can solve faster than current state of the art super computers? One such problem is the so called "Boson Sampling" problem introduced by Aaronson and Arkhipov. The problem is to generate random numbers according to same distribution as the output number configurations of photons in linear optics. It …
Charge Transfer Plasmon Resonances In Metallic Nanorod-Film Systems, Paul J. Gieri
Charge Transfer Plasmon Resonances In Metallic Nanorod-Film Systems, Paul J. Gieri
Shared Knowledge Conference
Understanding how the plasmonic response of colloidally grown metallic nanostructures changes when coupled to a metallic film is an important research problem with significant consequences for a number of applications such as sensing, solar energy harvesting, spectroscopy, and photochemistry, to name a few. In this work we investigate, both through experimental and theoretical approaches, the optical response of ligand coated gold nanorods and their interaction with gold films. We find that the scattering response of these systems is dominated by a charge transfer plasmon, in which charge flows between the particle and film. Additionally, we show that the characteristics of …
Pulsed Fiber Optics Lasers As Highly Sensitive Sensors, Hanieh Afkhamiardakani
Pulsed Fiber Optics Lasers As Highly Sensitive Sensors, Hanieh Afkhamiardakani
Shared Knowledge Conference
An interferometer or resonator is a device in which optical beams of specific frequencies circulate with minimal losses. These losses are completely compensated by the gain inside a laser resonator. A small perturbation introduced inside the laser can affect its frequency, which in turns becomes a metric of that perturbation. The perturbation is usually caused by an electric or magnetic field, rotation, acceleration, nonlinear index of refraction etc. Tiny changes of optical frequency are monitored by superimposing the laser field and a reference field (from the same laser) on a detector. This technique requires creating a laser in which two …
Cementitious Sensors Exhibiting Stopbands In Acoustic Transmission Spectra, Shreya Vemuganti
Cementitious Sensors Exhibiting Stopbands In Acoustic Transmission Spectra, Shreya Vemuganti
Shared Knowledge Conference
Ultrasonic monitoring in cementitious materials is challenging due to the high degree of attenuation. In wellbore environments, monitoring becomes more challenging due to inaccessibility. Meta materials, also known as acoustic bandgap materials, exhibit an interesting feature of forbidding the propagation of elastic/sound waves and isolate vibration in a certain frequency band. Traditionally, acoustic bandgap materials are developed with inclusions such as tin, aluminum, gold, steel in a polymer matrix. In this study, we present the development of three-dimensional cementitious sensors capable of exhibiting stopbands in the acoustic transmission spectra using carbon nanotubes. Relatively wide stopbands were engineered using Floquet-Bloch periodic …
Two Applications Of High Order Methods: Wave Propagation And Accelerator Physics, Oleksii Beznosov
Two Applications Of High Order Methods: Wave Propagation And Accelerator Physics, Oleksii Beznosov
Shared Knowledge Conference
Numerical simulations of partial differential equations (PDE) are used to predict the behavior of complex physics phenomena when the real life experiments are expensive. Discretization of a PDE is the representation of the continuous problem as a discrete problem that can be solved on a computer. The discretization always introduces a certain inaccuracy caused by the numerical approximation. By increasing the computational cost of the numerical algorithm the solution can be computed more accurately. In the theory of numerical analysis this fact is called the convergence of the numerical algorithm. The idea behind high order methods is to improve the …