Browsing by Author "Lisesivdin, S. B."
Now showing items 1-20 of 38
-
Ab initio study of electronic properties of armchair graphene nanoribbons passivated with heavy metal elements
Narin, P.; Abbas, J. M.; Atmaca, G.; Kutlu, E.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier, 2019)In this study, electronic properties of graphene nanoribbons with armchair edges (AGNRs) have been investigated with Density Functional Theory (DFT). Effects of heavy metal (HM) elements, including Zinc (Zn), Cadmium (Cd) ... -
Ab initio study of Ru-terminated and Ru-doped armchair graphene nanoribbons
Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.; Özbay, Ekmel (Taylor and Francis, 2012)We investigate the effects of ruthenium (Ru) termination and Ru doping on the electronic properties of armchair graphene nanoribbons (AGNRs) using first-principles methods. The electronic band structures, geometries, density ... -
Contributions of impurity band and electron-electron interactions to magnetoconductance in AlGaN
Tasli, P.; Yildiz, A.; Kasap, M.; Özbay, Ekmel; Lisesivdin, S. B.; Ozcelik, S. (Taylor & Francis, 2010-06-30)Low temperature electrical measurements of conductivity, the Hall effect and magnetoconductance were performed on a degenerate AlGaN sample. The sample exhibited negative magnetoconductance at low magnetic fields and low ... -
Determination of the critical indium composition corresponding to the metal-insulator transition in InxGa1-xN (0.06 ≤ x ≤ 0.135) layers
Yildiz, A.; Lisesivdin, S. B.; Tasli, P.; Özbay, Ekmel; Kasap, M. (Elsevier, 2009-10-13)The low-temperature conductivity of InxGa1-xN alloys (0.06 ≤ x ≤ 0.135) is analyzed as a function of indium composition (x). Although our InxGa1-xN alloys were on the metallic side of the metal-insulator transition, neither ... -
Determination of the LO phonon energy by using electronic and optical methods in AIGaN/GaN
Celik, O.; Tiras, E.; Ardali, S.; Lisesivdin, S. B.; Özbay, Ekmel (Springer, 2012)The longitudinal optical (LO) phonon energy in AlGaN/GaN heterostructures is determined from temperature-dependent Hall effect measurements and also from Infrared (IR) spectroscopy and Raman spectroscopy. The Hall effect ... -
Determination of two-dimensional electron and hole gas carriers in AlGaN/GaN/AlN heterostructures grown by Metal Organic Chemical Vapor Deposition
Acar, S.; Lisesivdin, S. B.; Kasap, M.; Özcelik, S.; Özbay, Ekmel (Elsevier BV, 2008-02-29)Resistivity and Hall effect measurements on nominally undoped Al0.25Ga0.75N/GaN/AlN heterostructures grown on sapphire substrates prepared by metal organic chemical vapor deposition have been carried out as a function of ... -
Double subband occupation of the two-dimensional electron gas in InxAl1-XN/AlN/GaN/AlN heterostructures with a low indium content (0.064 ≤ x ≤ 0.140) barrier
Lisesivdin, S. B.; Tasli, P.; Kasap, M.; Ozturk, M.; Arslan, E.; Ozcelik, S.; Özbay, Ekmel (Elsevier, 2010-05-08)We present a carrier transport study on low indium content (0.064 ≤ x ≤ 0.140) InxAl1 - xN/AlN/GaN/AlN heterostructures. Experimental Hall data were carried out as a function of temperature (33-300 K) and a magnetic field ... -
DX-center energy calculation with quantitative mobility spectrum analysis in n-AlGaAs/GaAs structures with low Al content
Lisesivdin, S. B.; Altuntas, H.; Yildiz, A.; Kasap, M.; Özbay, Ekmel; Ozcelik, S. (ELSEVIER, 2009-03-17)Experimental Hall data that were carried out as a function of temperature (60-350 K) and magnetic field (0-1.4 T) were presented for Si-doped low Al content (x=0.14) n-AlxGa1-xAs/GaAs heterostructures that were grown by ... -
The effect of AlN interlayer thicknesses on scattering processes in lattice-matched AlInN/GaN two-dimensional electron gas heterostructures
Teke, A.; Gökden, S.; Tülek, R.; Leach, J.H.; Fan, Q.; Xie, J.; Özgür, Ü.; Morkoç, H.; Lisesivdin, S. B.; Özbay, Ekmel (Institute of Physics Publishing Ltd., 2009)The scattering mechanisms governing the transport properties of high mobility AllnN/AlN/GaN two-dimensional electron gas (2DEG) heterostructures with various AIN spacer layer thicknesses from zero to 2 nm were presented. ... -
The effect of InxGa1−xN back-barriers on the dislocation densities in Al0.31Ga0.69N/AlN/GaN/InxGa1−xN/GaN heterostructures (0.05 ≤ x ≤ 0.14)
Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier, 2013-01)Al0.31Ga0.69N/AlN/GaN/InxGa1-xN/GaN heterostructures grown with the metal-organic chemical vapor deposition (MOCVD) technique with different InxGa1-xN back-barriers with In mole fractions of 0.05 <= x <= 0.14 were investigated ... -
Effect of substitutional as impurity on electrical and optical properties of β-Si3N4 structure
Kutlu, E.; Narin, P.; Atmaca, G.; Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier Ltd, 2016)β-Si3N4 is used as the gate dielectric for surface passivation in GaN-based, high-electron mobility transistors(HEMTs). In this study, the electrical and optical characteristics of the hexagonal β-Si3N4 crystal structure ... -
Effect of various pseudomorphic AIN layer insertions on the electron densities of two-dimensional electron gas in lattice-matched In0.18AI0.82N/GaN based heterostructures
Lisesivdin, S. B.; Özbay, Ekmel (Institutul National de Cercetare-Dezvoltare pentru Optoelectronica, 2009)We explored the effects of various pseudomorphic AlN layer insertions in lattice-matched In0.18Al0.82N/GaN based heterostructures on band structures and carrier densities with the help of one-dimensional self-consistent ... -
Electronic and optical properties of black phosphorus doped with Au, Sn and I atoms
Kutlu, E.; Narin, P.; Lisesivdin, S. B.; Özbay, Ekmel (Taylor and Francis, 2018)In this study, the electronic and the optical properties of monolayer black phosphorus (BP) doped with Gold (Au), Tin (Sn) and Iodine (I) atoms have been investigated by the density-functional theory (DFT) method. In the ... -
Electronic properties of graphene nanoribbons doped with zinc, cadmium, mercury atoms
Ömeroğlu, O.; Kutlu, E.; Narin, P.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier B.V., 2018)The effect of substitutional impurities as Zinc (Zn), Cadmium (Cd) and Mercury (Hg) on electronic properties of graphene nanoribbons (GNRs) was investigated by using Density Functional Theory (DFT). A substantial change ... -
Electronic properties of Li-doped zigzag graphene nanoribbons
Narin, P.; Kutlu, E.; Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier B.V., 2016)Zigzag graphene nanoribbons (ZGNRs) are known to exhibit metallic behavior. Depending on structural properties such as edge status, doping and width of nanoribbons, the electronic properties of these structures may vary. ... -
Electronic properties of zigzag ZnO nanoribbons with hydrogen and magnesium passivations
Abbas, J. M..; Narin, P.; Kutlu, E.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier, 2018)In this study, the electronic properties of ZnO nanoribbons with zigzag edges (ZZnONr) have been investigated with Density Functional Theory (DFT). After a geometric optimization, the electronic band structures, the density ... -
Electronic transport characterization of AlGaN∕GaN heterostructures using quantitative mobility spectrum analysis
Lisesivdin, S. B.; Yildiz, A.; Acar, S.; Kasap, M.; Ozcelik, S.; Özbay, Ekmel (AIP Publishing LLC, 2007-09-06)Resistivity and Hall effect measurements in nominally undoped Al0.25Ga0.75N/GaN heterostructures grown on sapphire substrate by metal-organic chemical vapor deposition are carried out as a function of temperature (20-350 ... -
Energy relaxation of electrons in InGaN quantum wells
Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.; Balkan, N.; Atmaca, G.; Narin, P.; Cakmak, H.; Özbay, Ekmel (Springer New York LLC, 2015-04)In this study, electron energy relaxation mechanisms in HEMT structures with different InxGa1−xN-channel quantum well (QW) widths are investigated. Theoretical value of the inelastic scattering rates is carried out at ... -
Extraction and scattering analyses of 2D and bulk carriers in epitaxial graphene-on-SiC structure
Lisesivdin, S. B.; Atmaca, G.; Arslan, E.; Çakmakyapan S.; Kazar, Ö.; Bütün, S.; Ul-Hassan, J.; Janzén, E.; Özbay, Ekmel (Elsevier BV, 2014-09)Hall effect measurements of a graphene-on-SiC system were carried out as a function of temperature (1.8-200 K) at a static magnetic field (0.51) With the analysis of temperature dependent single-field Hall data with the ... -
First-principles calculations of Pd-terminated symmetrical armchair graphene nanoribbons
Kuloglu, A. F.; Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.; Özbay, Ekmel (Elsevier, 2013)The effects of Palladium (Pd) termination on the electronic properties of armchair graphene nanoribbons (AGNRs) were calculated by using ab initio calculations. After a geometric optimization process, the electronic band ...