Browsing by Subject "Plasmon resonances"

Now showing 1 - 5 of 5

Open Access
Dynamic tuning of plasmon resonance in the visible using graphene
(The Optical Society, 2016) Balci, S.; Balci, O.; Kakenov, N.; Atar, F. B.; Kocabas, C.
We report active electrical tuning of plasmon resonance of silver nanoprisms (Ag NPs) in the visible spectrum. Ag NPs are placed in close proximity to graphene which leads to additional tunable loss for the plasmon resonance. The ionic gating of graphene modifies its Fermi level from 0.2 to 1 eV, which then affects the absorption of graphene due to Pauli blocking. Plasmon resonance frequency and linewidth of Ag NPs can be reversibly shifted by 20 and 35 meV, respectively. The coupled graphene-Ag NPs system can be classically described by a damped harmonic oscillator model. Atomic layer deposition allows for controlling the graphene-Ag NP separation with atomic-level precision to optimize coupling between them.
Open Access
Enhancement of plasmon resonances in the wave scattering by finite grids of circular silver wires
(IEEE, 2010-09) Natarov, D. M.; Benson, T. M.; Altıntaş, Ayhan; Sauleau, R.; Nosich, A. I.
Using the field expansions in local coordinates and addition theorems for cylindrical functions, we consider the problem of the H-polarized plane wave scattered by a finite chain of circular wires. The absorption and scattering cross-sections are found numerically and plasmon and grating-type resonances are studied for the grids of silver nano-size wires. © 2010 IEEE.
Open Access
Grating coupler integrated photodiodes for plasmon resonance based sensing in fluidic systems
(IEEE, 2011) Türker, Burak; Güner, Hasan; Ayaş, Sencer; Ekiz, Okan O.; Acar, Handan; Güler, Mustafa O.; Dâna, Aykutlu
We demonstrate an integrated sensor combining a grating-coupled plasmon resonance surface with a planar photodiode. Plasmon enhanced transmission is employed as a sensitive refractive index (RI) sensing mechanism and monitored via the integrated photodiode. © 2011 OSA.
Open Access
Tunable surface plasmon resonance on an elastomeric substrate
(Optical Society of American (OSA), 2009-05) Olcum, Selim; Kocabaş, Aşkın; Ertaş, Gülay; Atalar, Abdullah; Aydınlı, Atilla
In this study, we demonstrate that periods of metallic gratings on elastomeric substrates can be tuned with external strain and hence are found to control the resonance condition of surface plasmon polaritons. We have excited the plasmon resonance on the elastomeric grating coated with gold and silver. The grating period is increased up to 25% by applying an external mechanical strain. The tunability of the elastomeric substrate provides the opportunity to use such gratings as efficient surface enhanced Raman spectroscopy substrates. It's been demonstrated that the Raman signal can be maximized by applying an external mechanical strain to the elastomeric grating. © 2009 Optical Society of America.
Open Access
Understanding the plasmonic properties of dewetting formed Ag nanoparticles for large area solar cell applications
(Optical Society of American (OSA), 2013) Günendi, M.C.; Tanyeli I.; Akgüç G.B.; Bek, A.; Turan, R.; Gülseren O.
The effects of substrates with technological interest for solar cell industry are examined on the plasmonic properties of Ag nanoparticles fabricated by dewetting technique. Both surface matching (boundary element) and propagator (finite difference time domain) methods are used in numerical simulations to describe plasmonic properties and to interpret experimental data. The uncertainty on the locations of nanoparticles by the substrate in experiment is explained by the simulations of various Ag nanoparticle configurations. The change in plasmon resonance due to the location of nanoparticles with respect to the substrate, interactions among them, their shapes, and sizes as well as dielectric properties of substrate are discussed theoretically and implications of these for the experiment are deliberated. ©2013 Optical Society of America.