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  New high-resolution display device for holographic three-dimensional video: principles and simulations 

  Onural, Levent; Bozdağı, Gözde; Atalar, Abdullah (Bilkent University, 2017-08-03)

  A new acousto-optical holographic display device, which is expected to solve the display resolution and refresh problems that are common to available holographic displays, is proposed. The device is based on the ...
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  An improved lumped element nonlinear circuit model for a circular CMUT cell 

  Koymen, H.; Atalar, A.; Aydogdu, E.; Kocabas, C.; Oguz, H. K.; Olcum, S.; Ozgurluk, A.; Unlugedik, A. (IEEE, 2012-08)

  This paper describes a correction and an extension in the previously published large signal equivalent circuit model for a circular capacitive micromachined ultrasonic transducer (CMUT) cell. The force model is rederived ...
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  High-speed >90% quantum-efficiency p–i–n photodiodes with a resonance wavelength adjustable in the 795–835 nm range 

  Ozbay, E.; Kimukin, I.; Biyikli, N.; Aytur, O.; Gokkavas, M.; Ulu, G.; Unlu, M. S.; Mirin, R.; Bertness, K. A.; Christensen, D. H. (American Institute of Physics, 1999)

  We report GaAs/AlGaAs-based high-speed, high-efficiency, resonant cavity enhanced p–i–nphotodiodes. The devices were fabricated by using a microwave-compatible fabrication process. By using a postprocess recess etch, we ...
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  Plasmon-based photopolymerization: near-field probing, advanced photonic nanostructures and nanophotochemistry 

  Zhou, X.; Sppera, O.; Plain, J.; Jradi, S.; Sun, X. W.; Demir, H. V.; Yang, X.; Deeb, C.; Gray, S.; Wiederrecht, G.; Bachelot, R. (IOP Publishing, 2014-11-03)

  Hybrid nanomaterials are targeted by a rapidly growing group of nanooptics researchers, due to the promise of optical behavior that is difficult or even impossible to create with nanostructures of homogeneous composition. ...
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  Light extraction efficiency enhancement of colloidal quantum dot light-emitting diodes using large-scale nanopillar arrays 

  Yang, X.; Dev, K.; Wang, J.; Mutlugun, E.; Dang, C.; Zhao, Y.; Liu, S.; Tang, Y.; Tan, S. T.; Sun, X. W.; Demir, H. V. (Wiley-VCH Verlag, 2014)

  A colloidal quantum dot light-emitting diode (QLED) is reported with substantially enhanced light extraction efficiency by applying a layer of large-scale, low-cost, periodic nanopillar arrays. Zinc oxide nanopillars are ...
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  Enhanced efficiency of solution-processed small-molecule solar cells upon incorporation of gold nanospheres and nanorods into organic layers 

  Xu, X.; Kyaw, A. K. K.; Peng, B.; Du, Q.; Hong, L.; Demir, H. V.; Wong, T. K. S.; Xiong, Q.; Sun, X. W. (Royal Society of Chemistry, 2014)

  The significantly enhanced performance upon incorporation of Au nanoparticles in solution-processed small-molecule solar cells is demonstrated. Simultaneously incorporating Au nanospheres into the hole transport layer and ...
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  Green/Yellow Solid State Lighting via Radiative and Nonradiative Energy Transfer Involving Colloidal Semiconductor Nanocrystals 

  Nizamoglu, S.; Sari, E.; Baek, J. H.; I H; Lee; Demir, H. V. (IEEE, 2009)

  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, ...
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  Colloidal Nanocrystals Embedded in Macrocrystals: Robustness, Photostability, and Color Purity 

  Otto, T.; Mueller, M.; Mundra, P.; Lesnyak, V.; Demir, H. V.; Gaponik, N.; Eychmuller, A. (American Chemical Society, 2012-09-14)

  The incorporation of colloidal quantum dots (QDs) into ionic crystals of various salts (NaCl, KCl, KBr, etc.) is demonstrated. The resulting mixed crystals of various shapes and beautiful colors preserve the strong ...
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  Excitation resolved color conversion of CdSe/ZnS core/shell quantum dot solids for hybrid white light emitting diodes 

  Nizamoglu, S.; Demir, H. V. (American Institute of Physics, 2009)

  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 ...
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  On the triplet distribution and its effect on an improved phosphorescent organic light-emitting diode 

  Liu, S. W.; Divayana, Y.; Abiyasa, A. P.; Tan, S. T.; Demir, H. V.; Sun, X. W. (AIP Publishing, 2012)

  We reported phosphorescent organic light-emitting diodes with internal quantum efficiency near 100% with significantly reduced efficiency roll-off. It was found that the use of different hole transporting layer (HTL) affects ...
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  Electric field dependent radiative decay kinetics of polar InGaN/GaN quantum heterostructures at low fields 

  Sari, E.; Nizamoglu, S.; Lee, I. H.; Baek, J. H.; Demir, H. V. (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 ...
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  Self-screening of the quantum confined Stark effect by the polarization induced bulk charges in the quantum barriers 

  Zhang, Z. H.; Li, W.; Ju, Z.; Tan, S. T.; Ji, Y.; Kyaw, Z.; Zhang, X.; Wang, L.; Sun, X. W.; Demir, H. V. (AIP Publishing, 2014)

  InGaN/GaN light-emitting diodes (LEDs) grown along the polar orientations significantly suffer from the quantum confined Stark effect (QCSE) caused by the strong polarization induced electric field in the quantum wells, ...
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  Excitonic enhancement of nonradiative energy transfer from a quantum well in the optical near field of energy gradient quantum dots 

  Nizamoglu, S.; Hernandez Martinez, P. L.; Mutlugun, E.; Karatay, D. U.; Demir, H. V. (American Institute of Physics, 2012)

  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) ...
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  Full Visible Range Covering InP/ZnS Nanocrystals with High Photometric Performance and Their Application to White Quantum Dot Light-Emitting Diodes 

  Yang, X.; Zhao, D.; Leck, K. S.; Tan, S. T.; Tang, Y. X.; Zhao, J.; Demir, H. V.; Sun, X. W. (Wiley-VCH Verlag, 2012-04-30)

  High-quality InP/ZnS core–shell nanocrystals with luminescence tunable over the entire visible spectrum have been achieved by a facile one-pot solvothermal method. These nanocrystals exhibit high quantum yields (above 60%), ...
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  Amplified Spontaneous Emission and Lasing in Colloidal Nanoplatelets 

  Guzelturk, B.; Kelestemur, Y.; Olutas, M.; Delikanli, S.; Demir, H. V. (American Chemical Society, 2014-07)

  Colloidal nanoplatelets (NPLs) have recently emerged as favorable light-emitting materials, which also show great potential as optical gain media due to their remarkable optical properties. In this work, we systematically ...
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  A bright cadmium-free, hybrid organic/quantum dot white light-emitting diode 

  Yang, X.; Divayana, Y.; Zhao, D.; Leck, K. S.; Lu, F.; Tan, S. T.; Abiyasa, A. P.; Zhao, Y.; Demir, H. V.; Sun, X. W. (American Institute of Physics, 2012)

  We report a bright cadmium-free, InP-based quantum dot light-emitting diode (QD-LED) with efficient green emission. A maximum brightness close to 700 cd/m(2) together with a relatively low turn-on voltage of 4.5 V has been ...
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  Dye-sensitized solar cell with a pairof carbon-based electrodes 

  Kyaw, A. K. K.; Tantang, H.; Wu, T.; Ke, L.; Wei, J.; Demir, H. V.; Zhang, Q.; Sun, X. W. (IOP Publishing, 2012-04-02)

  We have fabricated a dye-sensitized solar cell (DSSC) with a pair of carbon-based electrodes using a transparent, conductive carbon nanotubes (CNTs) film modified with ultra-thin titanium-sub-oxide (TiOx) as the working ...
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  Stacking in Colloidal Nanoplatelets: Tuning Excitonic Properties 

  Guzelturk, B.; Erdem, O.; Olutas, M.; Kelestemur, Y.; Demir, H. V. (American Chemical Society, 2014)

  Colloidal semiconductor quantum wells, also commonly known as nanoplatelets (NPLs), have arisen among the most promising materials for light generation and harvesting applications. Recently, NPLs have been found to assemble ...
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  On the origin of the redshift in the emission wavelength of InGaN/GaN blue light emitting diodes grown with a higher temperature interlayer 

  Ju, Z. G.; Tan, S. T.; Zhang, Z. H.; Ji, Y.; Kyaw, Z. B.; Dikme, Y.; Sun, X. W.; Demir, H. V. (AIP Publishing, 2012)

  A redshift of the peak emission wavelength was observed in the blue light emitting diodes of InGaN/GaN grown with a higher temperature interlayer that was sandwiched between the low-temperature buffer layer and high-temperature ...
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  Quantum efficiency enhancement in nanocrystals using nonradiative energy transfer with optimized donor-acceptor ratio for hybrid LEDs 

  Nizamoglu, S.; Akin, O.; Demir, H. V. (American Institute of Physics, 2009)

  The quantum efficiency enhancement in nanocrystal solids is critically important for their efficient use as luminophors on color-conversion light emitting diodes (LEDs). For this purpose, we investigate energy gradient ...

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