Recent Submissions

  • Future outlook 

    Erdem, Talha; Demir, Hilmi Volkan (Springer, 2019-01)
    In this final Chapter, we present a future perspective for the light source design. We discuss the existing problems and briefly introduce new material systems and device architectures that can overcome the current issues.
  • How to design quality light sources with discrete color components 

    Erdem, Talha; Demir, Hilmi Volkan (Springer, 2019-01)
    White light sources using discrete emitters require careful design and optimization. The first step of the design should be determining the intended use of the light source so that application specific requirements can be ...
  • Common white light sources 

    Erdem, Talha; Demir, Hilmi Volkan (Springer, 2019-01)
    In this Chapter we describe the features of common light sources. We first present the spectral features of the sun and discuss its colorimetric properties. Next, we summarize the properties of traditional light sources ...
  • Metrics for light source design 

    Erdem, Talha; Demir, Hilmi Volkan (Springer, 2019-01)
    In this part of this brief, we summarize the metrics that need to be considered for designing light sources. We start with metrics on the shade of color and then continue with color rendering and photometry.
  • Colorimetry for LED lighting 

    Erdem, Talha; Demir, Hilmi Volkan (Springer, 2019-01)
    In this Chapter, we explain the basics of colorimetry and introduce the colorimetric tools useful for designing light sources.
  • Light stimulus and human eye 

    Erdem, Talha; Demir, Hilmi Volkan (Springer, 2019-01)
    In this Chapter, we summarize the structure of the human eye and introduce the sensitivity functions of various photoreceptors and present the visual regimes and corresponding eye sensitivity functions.
  • The biobjective multiarmed bandit: learning approximate lexicographic optimal allocations 

    Tekin, Cem (TÜBİTAK, 2019-03)
    We consider a biobjective sequential decision-making problem where an allocation (arm) is called ϵ lexicographic optimal if its expected reward in the first objective is at most ϵ smaller than the highest expected reward, ...
  • Effects of the AlN nucleation layer thickness on the crystal structures of an AlN epilayer grown on the 6H-SiC substrate 

    Arslan, Engin; Öztürk, M. K.; Özçelik, S.; Özbay, Ekmel (Taylor & Francis, 2019-04-08)
    The influence of the LT-AlN(NL) growth times on the mosaic structure parameters of the AlN layer grown on the LT-AlN(NL)/6H-SiC structures as well as the dislocation densities and the strain behaviours in the AlN epilayers ...
  • Investigation of electronic and optical properties of wurtzite MgZnO using GGA + U formalism 

    Ibrahem, R.; Narin, P.; Lisesivdin, S. B.; Özbay, Ekmel (Taylor & Francis, 2019-12-04)
    In this study, the electronic and optical properties of wurtzite MgxZn1−xO structures for different Mg mole fractions (x) are studied using Density Functional Theory (DFT). In calculations, the generalised gradient ...
  • Two-dimensional phononic band structure of archimedean-logarithmic spiral-based slabs 

    Palaz, S.; Oltulu, O.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-08-16)
    We present band structure results for elastic waves in periodic composite materials consisting of a spiral scatterer shape embedded in a uniform silicon matrix. The material of the scatterer is tungsten as a high density ...
  • Multiferroic based 2D phononic crystals: band structure and wave propagations 

    Palaz, S.; Özer, Z.; Ahundov, C.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-08)
    In the present work the acoustic band structure of a two-dimensional phononic crystal containing an organic ferroelectric (PVDF- polyvinylidene fluoride) and muliferroic material (LiVCuO4) were investigated by the ...
  • Electronic and elastic properties of the multiferroic crystals with the Kagome type lattices -Mn3V2O8 and Ni3V2O8: First principle calculations 

    Koç, H.; Palaz, S.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-08-16)
    The electronic, mechanical, and optical properties of the Kagome staircase compounds, Mn3V2O8 and Ni3V2O8, have been investigated using the VASP (Vienna ab-initio Simulation Program) that was developed within the density ...
  • Strain effects and electronic structures of narrow band P-R ferroelectrics: first principles calculation 

    Bozdağ, N.; Koç, H.; Şimşek, Ş.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-08-16)
    In the present work, the structural, mechanical, electronic and optical properties of the Ruddlesden–Popper(RP) Ba3X2S7 (X = Zr, Hf, Ti) sulfides compounds have been investigated by means of first principles calculations. ...
  • Phononic band gap and wave propagation on multiferroic-based acoustic metamaterials 

    Palaz, S.; Oltulu, O.; Özer, Z.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-06-04)
    In the present work, the acoustic band structure of a two-dimensional (2D) phononic crystal containing a multiferroic and liquid were investigated by the plane-wave-expansion method. 2D PnC with triangular and honeycomb ...
  • Photonic band gap of multiferroic-dielectric materials in the IR region: FDTD method 

    Palaz, S.; Şimşek, Ş.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-06-04)
    In this report, we present an investigation of the optical properties and band structure calculations for the photonic structures based on the multiferroic materials- BaMnF4. We calculate the photonic bands and optical ...
  • Electronic properties of spin excitation in multiferroics with a spinel structure: first principles calculation 

    Koç, H.; Palaz, S.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-06-04)
    In the present work, the structural, electronic and mechanical properties of LiVCuO4 and LiCu2O4 spinel type multiferroics have been investigated by means of first principles calculations. The spin polarized generalized ...
  • Structural, electronic, and mechanical properties of A3Mn2O7 (A = Sr, Ca): ab initio calculation 

    Şimsek, Ş.; Koç, H.; Mamedov, Amirullah M.; Özbay, Ekmel (Taylor & Francis, 2019-04-17)
    In the present study, the structural, electronic, optical, and mechanical properties of the Ruddlesden-Popper type oxide compounds are investigated by means of density functional theory. In our calculation, spin polarized ...
  • Scattering analysis of ultrathin barrier (<7 nm) GaN‑based heterostructures 

    Narin, P.; Arslan, Engin; Öztürk, M.; Öztürk, Mustafa; Lisesivdin, S. B.; Özbay, Ekmel (Springer, 2019-03)
    In this study, two-dimensional electron gas (2DEG) mobility analysis of AlN/GaN and InAlN/GaN structures with ultrathin barrier layers by metal organic chemical vapor deposition (MOCVD) has been performed with Hall efect ...
  • On the elastic properties of INGAN/GAN LED structures 

    Bilgili, A. K.; Akpınar, Ö.; Öztürk, M. K; Başköse, C.; Özçelik, S.; Özbay, Ekmel (Springer, 2019-01)
    In this study, three InGaN/GaN light-emitting diode (LED) structures with five periods are investigated grown by metal organic chemical vapor deposition (MOCVD) technique. During growth of these three samples, active layer ...
  • Investigation of structural, optical and morphological properties of InGaN/GaN structure 

    Bilgili, A. K.; Akpınar, Ö.; Öztürk, M. K; Başköse, C.; Özçelik, S.; Özbay, Ekmel (Springer, 2019)
    In this study, InGaN/GaN structure is investigated in the temperature range of 300–500 °C with steps of 50 °C. InGaN/ GaN multi-quantum well structure is deposited on c-orientated sapphire wafer by metal organic chemical ...

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