Browsing by Author "Nizamoglu, S."
Now showing items 1-20 of 39
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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 ... -
Blue quantum electroabsorption modulators based on reversed quantum confined Stark effect with blueshift
(AIP Publishing LLC, 2007-01-02)The authors present the design, growth, fabrication, experimental characterization, and theoretical analysis of blue quantum electroabsorption modulators that incorporate similar to 5 nm thick In0.35Ga0.65N/GaN quantum ... -
Color-converting combinations of nanocrystal emitters for warm-white light generation with high color rendering index
(American Institute of Physics, 2008-01-22)Warm-white light emitting diodes with high color rendering indices are required for the widespread use of solid state lighting especially indoors. To meet these requirements, we propose and demonstrate warm-white hybrid ... -
Computational study of power conversion and luminous efficiency performance for semiconductor quantum dot nanophosphors on light-emitting diodes
(Optical Society of America, 2012-01-30)We present power conversion efficiency (PCE) and luminous efficiency (LE) performance levels of high photometric quality white LEDs integrated with quantum dots (QDs) achieving an averaged color rendering index of >= 90 ... -
Dual-color emitting quantum-dot-quantum-well CdSe-ZnS heteronanocrystals hybridized on InGaN/GaN light emitting diodes for high-quality white light generation
(AIP Publishing LLC, 2008-03)We report white light generation by hybridizing green-red emitting (CdSeZnS/CdSe (core) shell/ shell quantum-dot-quantum-well heteronanocrystals on blue InGaN/GaN light emitting diodes with the photometric properties of ... -
Efficient nonradiative energy transfer from InGaN/GaN nanopillars to CdSe/ZnS core/shell nanocrystals
(AIP Publishing, 2011-04-20)In this study, we propose and demonstrate efficient electron-hole pair injection from InGaN/GaN multiple quantum well nanopillars (MQW-NPs) to CdSe/ZnS core/shell nanocrystal quantum dots (NQDs) via Forster-type nonradiative ... -
Electric field dependent radiative decay kinetics of polar InGaN/GaN quantum heterostructures at low fields
(American Institute of Physics, 2009-05-29)Electric field dependent photoluminescence decay kinetics and its radiative component are studied in polar InGaN/GaN quantum heterostructures at low fields. Under externally applied electric field lower than polarization ... -
Excitation resolved color conversion of CdSe/ZnS core/shell quantum dot solids for hybrid white light emitting diodes
(American Institute of Physics, 2009-04-28)In this paper, for their use as nanoluminophors on color-conversion white light emitting diodes (LEDs), we present spectrally resolved relative quantum efficiency and relative color (photon) conversion efficiency of CdSe/ZnS ... -
Excitonic enhancement of nonradiative energy transfer from a quantum well in the optical near field of energy gradient quantum dots
(American Institute of Physics, 2012-06-13)We report strong exciton migration with an efficiency of 83.3% from a violet-emitting epitaxial quantum well (QW) to an energy gradient colloidal construct of layered green-and red-emitting nanocrystal quantum dots (NQDs) ... -
Förster resonance energy transfer enhanced color-conversion using colloidal semiconductor quantum dots for solid state lighting
(American Institute of Physics, 2009-10-15)In this paper, we present Förster resonance energy transfer (FRET)-enhanced color-conversion using colloidal semiconductor quantum dot nanocrystals (NCs) to make reddish-orange light-emitting diodes for use in ultraefficient ... -
Green/yellow solid state lighting via radiative and nonradiative energy transfer involving colloidal semiconductor nanocrystals
(IEEE, 2009-08-05)LEDs made of In(x)Ga(1-x)N and (Al(x)Ga(1-x))(1-y)In(y)P suffer from significantly reduced quantum efficiency and luminous efficiency in the green/yellow spectral ranges. To address these problems, we present the design, ... -
High scotopic/photopic ratio white-light-emitting diodes integrated with semiconductor nanophosphors of colloidal quantum dots
(Optical Society of America, 2011)We propose and demonstrate single-chip white-light-emitting diodes (WLEDs) integrated with semiconductor nanophosphors of colloidal quantum dots for high scotopic/photopic (S/P) ratio. These color conversion WLEDs achieve ... -
Hybrid white light sources based on layer-by-layer assembly of nanocrystals on near-UV emitting diodes
(Institute of Physics Publishing Ltd., 2007-09-17)We present the design, growth, fabrication, integration and characterization of alternative hybrid white light sources based on the controlled layer-by-layer assembly of nanocrystals on UV-emitting nitride diodes for ... -
Localized plasmon-engineered spontaneous emission of CdSe/ZnS nanocrystals closely-packed in the proximity of Ag nanoisland films for controlling emission linewidth, peak, and intensity
(Optical Society of America, 2007)Using metallic nanoislands, we demonstrate the localized plasmonic control and modification of the spontaneous emission from closely-packed nanocrystal emitters, leading to significant changes in their collective emission ... -
Nanocrystal-based hybrid white light generation with tunable colour parameters
(Institute of Physics Publishing Ltd., 2007)We present the hybridization of CdSe/ZnS core-shell nanocrystals (NCs) on InGaN/GaN based blue/near-UV LEDs to generate light widely tunable across the visible spectral range and especially within the white region of the ... -
Nonradiative resonance energy transfer directed from colloidal CdSe/ZnS quantum dots to epitaxial InGaN/GaN quantum wells for solar cells
(Wiley, 2010-06-04)We report on Förster-type nonradiative resonance energy transfer (NRET) directed from colloidal quantum dots (QDs) to epitaxial quantum wells (QWs) with an efficiency of 69.6% at a rate of 1.527 ns-1 for potential application ... -
Observation of efficient transfer from Mott-Wannier to Frenkel excitons in a hybrid semiconductor quantum dot-polymer composite at room temperature
(American Institute of Physics, 2010-12-29)Efficient conversion from Mott-Wannier to Frenkel excitons is observed at room temperature. The time-resolved photoluminescence shows that the energy transfer rate and efficiency reach 0.262 ns-1 and 80.9%, respectively. ... -
Observation of selective plasmon-exciton coupling in nonradiative energy transfer: donor-selective versus acceptor-selective plexcitons
(American Chemical Society, 2013-06)We report selectively plasmon-mediated nonradiative energy transfer between quantum dot (QD) emitters interacting with each other via Forster-type resonance energy transfer (FRET) under controlled plasmon coupling either ... -
Onion-Like (CdSe)ZnS/CdSe/ZnS quantum-dot-quantum-well heteronanocrystals for investigation of multi-color emission
(Optical Society of America, 2008)We investigate multi-color spontaneous emission from quantum-dot-quantum-well heteronanocrystals made of onion-like (CdSe) ZnS/CdSe/ZnS ( core) shell/shell/shell structures, with our theoretical results explaining experimental ... -
Opposite carrier dynamics and optical absorption characteristics under external electric field in nonpolar vs. polar InGaN/GaN based quantum heterostructures
(Optical Society of America, 2011)We report on the electric field dependent carrier dynamics and optical absorption in nonpolar a-plane GaN-based quantum heterostructures grown on r-plane sapphire, which are surprisingly observed to be opposite to those ...
