Browsing by Keywords "Excitons"
Now showing items 1-20 of 39
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Absorption enhancement of molecules in the weak plasmon-exciton coupling regime
(Optical Society of American (OSA), 2014)We report on the experimental and theoretical investigations of enhancing the optical absorption of organic molecules in the weak plasmon-exciton coupling regime. A metal-organic hybrid structure consisting of dye molecules ... -
Anisotropic Emission from Multilayered Plasmon Resonator Nanocomposites of Isotropic Semiconductor Quantum Dots
(American Chemical Society, 2011-01-19)We propose and demonstrate a nanocomposite localized surface plasmon resonator embedded into an artificial three-dimensional construction. Colloidal semiconductor quantum dots are assembled between layers of metal nanoparticles ... -
Broadband optical transparency in plasmonic nanocomposite polymer films via exciton-plasmon energy transfer
(OSA - The Optical Society, 2016)Inherent absorptive losses affect the performance of all plasmonic devices, limiting their fascinating applications in the visible range. Here, we report on the enhanced optical transparency obtained as a result of the ... -
Colloidal nanoplatelet/conducting polymer hybrids: excitonic and material properties
(American Chemical Society, 2016)Here we present the first account of conductive polymer/colloidal nanoplatelet hybrids. For this, we developed DEH-PPV-based polymers with two different anchor groups (sulfide and amine) acting as surfactants for CdSe ... -
Colloidal quantum dot light-emitting diodes employing phosphorescent small organic molecules as efficient exciton harvesters
(American Chemical Society, 2014)Nonradiative energy transfer (NRET) is an alternative excitation mechanism in colloidal quantum dot (QD) based electroluminescent devices (QLEDs). Here, we develop hybrid highly spectrally pure QLEDs that facilitate energy ... -
Conditions for observation of Rabi oscillations in an exciton-polariton system
(Elsevier BV, 1995)The pure quantum model describing Rabi oscillations of exciton-polaritons (EP) in a micro-cavity with finite quality is considered. It is shown that the oscillations can be observed if the cavity damping rate does not ... -
Critical role of CdSe nanoplatelets in color-converting CdSe/ZnS nanocrystals for InGaN/GaN light-emitting diodes
(OSA - The Optical Society, 2016)Here we report CdSe nanoplatelets that are incorporated into color-converting CdSe/ZnS nanocrystals for InGaN/GaN light-emitting diodes. The critical role of CdSe nanoplatelets as an exciton donor for the color conversion ... -
Determination of energy-band offsets between GaN and AlN using excitonic luminescence transition in AlGaN alloys
(American Institute of PhysicsA I P Publishing LLC, 2006)We report the determination of the energy-band offsets between GaN and AlN using the linewidth (full width at half maximum) of an extremely sharp excitonic luminescence transition in Alx Ga1-x N alloy with x=0.18 at 10 K. ... -
Electronic structure of conducting organic polymers: insights from time-dependent density functional theory
(John Wiley & Sons Ltd., 2014)Conducting organic polymers (COPs) became an active field of research after it was discovered how thin films rather than insoluble infusible powders can be produced. The combination of the properties of plastics with those ... -
Enhanced exciton transfer from the cascaded bilayer of green-and red-emitting CdTe quantum dots into bulk silicon
(Optical Society of America, 2013)We show enhanced transfer of excitons from the energy-gradient of bilayered green/red-emitting quantum dots into silicon using cascaded nonradiative energy with an overall enhancement factor of 1.3 at room temperature for ... -
Enhanced spontaneous emission in semiconductor nanocrystal solids using resonant energy transfer for integrated devices
(IEEE, 2008-11)Size-tuneable optical properties of semiconductor nanocrystal (NC) quantum dots make them attractive for a wide range of device applications. However, in these device applications, nanocrystals typically suffer from ... -
Exciton induced directed motion of unconstrained atoms in an ultracold gas
(Institute of Physics Publishing, 2017)We demonstrate that through localised Rydberg excitation in a three-dimensional cold atom cloud atomic motion can be rendered directed and nearly confined to a plane, without spatial constraints for the motion of individual ... -
Excitonic condensation under spin-orbit coupling and BEC-BCS crossover
(The American Physical Society, 2007)The condensation of electron-hole pairs is studied at zero temperature and in the presence of a weak spin-orbit coupling (SOC) in coupled quantum wells. Under realistic conditions, a perturbative SOC can have observable ... -
Excitonic energy transfer dynamics in hybrid organic/inorganic nanocomposites at high loading levels
(Optical Society of America, 2012)Temperature dependent exciton migration in the hybrid nanocomposites of conjugated polymers chemically integrated with quantum dots is studied at high loading levels. The underlying interplay between the exciton transfer ... -
Green stimulated emission boosted by nonradiative resonant energy transfer from blue quantum dots
(American Chemical Society, 2016)Thanks to their tunability and versatility, the colloidal quantum dots (CQDs) made of II-VI semiconductor compound offer the potential to bridge the "green gap" in conventional semiconductors. However, when the CQDs are ... -
Increased quantum efficiency and reduced red-shift in polymer nanoparticle luminophors
(IEEE, 2008-11)In this paper, using a polyfluorene derivative, increased fluorescence quantum efficiency and reduced red-shift in the film form of polymer nanoparticle luminophors is achieved, when compared to directly spin coated polymer ... -
Large-Area (over 50 cm × 50 cm) Freestanding Films of Colloidal InP/ZnS Quantum Dots
(American Chemical Society, 2012)We propose and demonstrate the fabrication of flexible, freestanding films of InP/ZnS quantum dots (QDs) using fatty acid ligands across very large areas (greater than 50 cm x 50 cm), which have been developed for remote ... -
Light matter interaction in plexcitonic crystals and moiré cavities
(Bilkent University, 2015-01)Surface plasmon polaritons (SPPs) are quanta of electromagnetic excitations at the interface between metal and dielectric media. SPPs with an evanescent tail in the perpendicular direction, thus their properties are ... -
Light-induced paramagnetism in colloidal Ag+-doped CdSe nanoplatelets
(American Chemical Society, 2021-03-25)We describe a study of the magneto-optical properties of Ag+-doped CdSe colloidal nanoplatelets (NPLs) that were grown using a novel doping technique. In this work, we used magnetic circularly polarized luminescence and ... -
Monte Carlo simulation of localization dynamics of excitons in ZnO and CdZnO quantum well structures
(American Institute of Physics, 2006)Localization dynamics of excitons was studied for ZnOMgZnO and CdZnOMgZnO quantum wells (QWs). The experimental photoluminescence (PL) and absorption data were compared with the results of Monte Carlo simulation in which ...
