Now showing items 1-18 of 18

    • Atomic structure of the √3 × √3 phase of silicene on Ag (111) 

      Cahangirov, S.; Özçelik, V. O.; Xian, L.; Avila, J.; Cho, S.; Asensio, M. C.; Çıracı, Salim; Rubio, A. (American Physical Society, 2014-07-28)
      The growth of the 3√×3√ reconstructed silicene on Ag substrate has been frequently observed in experiments while its atomic structure and formation mechanism is poorly understood. Here, by first-principles calculations, ...
    • Effects of charging and perpendicular electric field on the properties of silicene and germanene 

      Gürel, H. H.; Özçelik, V. O.; Çıracı, Salim (Institute of Physics Publishing, 2013)
      Using first-principles density functional theory calculations, we showed that electronic and magnetic properties of bare and Ti adatom adsorbed single-layer silicene and germanene, which are charged or subjected to a ...
    • Epitaxial growth mechanisms of graphene and effects of substrates 

      Özçelik, V. O.; Cahangirov, S.; Çıracı, Salim (American Physical Society, 2012)
      The growth process of single layer graphene with and without substrate is investigated using ab initio, finite temperature molecular dynamic calculations within density functional theory. An understanding of the epitaxial ...
    • High-performance planar nanoscale dielectric capacitors 

      Özçelik, V. O.; Çıracı, Salim (American Physical Society, 2015)
      We propose a model for planar nanoscale dielectric capacitors consisting of a single layer, insulating hexagonal boron nitride (BN) stripe placed between two metallic graphene stripes, all forming commensurately a single ...
    • Local reconstructions of silicene induced by adatoms 

      Özçelik, V. O.; Çıracı, Salim (American Chemical Society, 2013)
      The interaction of silicene with Si, C, H, O, and Ti atoms along with H2, H2O, and O2 molecules are investigated and the induced functionalities thereof are analyzed using first principles density functional theory. Si ...
    • Modulation of electronic properties in laterally and commensurately repeating graphene and boron nitride composite nanostructures 

      Özçelik, V. O.; Durgun, Engin; Çıracı, Salim (American Chemical Society, 2015)
      Graphene and hexagonal boron nitride (h-BN) nanoribbons of diverse widths and edge geometries are laterally repeated to form commensurate, single-layer, hybrid honeycomb structures. The resulting composite materials appear ...
    • Nanoscale dielectric capacitors composed of graphene and boron nitride layers: a first-principles study of high capacitance at nanoscale 

      Özçelik, V. O.; Çıracı, Salim (American Chemical Society, 2013)
      We investigate a nanoscale dielectric capacitor model consisting of two-dimensional, hexagonal h-BN layers placed between two commensurate and metallic graphene layers using self-consistent field density functional theory. ...
    • New phases of germanene 

      Özçelik, V. O.; Durgun, Engin; Çıracı, Salim (American Chemical Society, 2014)
      Germanene, a graphene-like single-layer structure of Ge, has been shown to be stable and recently grown on Pt and Au substrates. We show that a Ge adatom adsorbed on germanene pushes down the host Ge atom underneath and ...
    • Prediction of a two-dimensional crystalline structure of nitrogen atoms 

      Özçelik, V. O.; Aktürk, O. U.; Durgun, Engin; Çıracı, Salim (American Physical Society, 2015)
      Based on first-principles density functional calculations, we predict that nitrogen atoms can form a single-layer, buckled honeycomb structure called nitrogene, which is rigid and stable even above room temperature. This ...
    • Self-assembly mechanisms of short atomic chains on single-layer graphene and boron nitride 

      Özçelik, V. O.; Çıracı, Salim (American Physical Society, 2012)
      Nucleation and growth mechanisms of short chains of carbon atoms on single-layer, hexagonal boron nitride (h-BN) and short BN chains on graphene are investigated using first-principles plane-wave calculations. Our analysis ...
    • Self-healing of vacancy defects in single-layer graphene and silicene 

      Özçelik, V. O.; Gurel, H. H.; Çıracı, Salim (American Physical Society, 2013)
      Self-healing mechanisms of vacancy defects in graphene and silicene are studied using first-principles calculations. We investigated host adatom adsorption, diffusion, vacancy formation, and revealed atomistic mechanisms ...
    • Silicite: the layered allotrope of silicon 

      Cahangirov, S.; Özçelik, V. O.; Rubio, A.; Çıracı, Salim (American Physical Society, 2014)
      Based on first-principles calculations, we predict two new thermodynamically stable layered-phases of silicon, named as silicites, which exhibit strong directionality in the electronic and structural properties. As compared ...
    • Single-layer crystalline phases of antimony: Antimonenes 

      Aktürk, O. Ü.; Özçelik, V. O.; Çıracı, Salim (American Physical Society, 2015)
      The pseudolayered character of 3D bulk crystals of antimony has led us to predict its 2D single-layer crystalline phase named antimonene in a buckled honeycomb structure like silicene. Sb atoms also form an asymmetric ...
    • Size dependence in the stabilities and electronic properties of α-graphyne and its boron nitride analogue 

      Özçelik, V. O.; Çıracı, Salim (American Chemical Society, 2013)
      We predict the stabilities of α-graphynes and their boron nitride analogues (α-BNyne), which are considered as competitors of graphene and two-dimensional hexagonal BN. On the basis of the first-principles plane wave method, ...
    • Stable single-layer honeycomblike structure of silica 

      Özçelik, V. O.; Cahangirov, S.; Çıracı, Salim (American Physical Society, 2014)
      Silica or SiO2, the main constituent of Earth's rocks has several 3D complex crystalline and amorphous phases, but it does not have a graphitelike layered structure in 3D. Our theoretical analysis and numerical calculations ...
    • Structure dependent optoelectronic properties of monolayer antimonene, bismuthene and their binary compound 

      Kecik, Deniz; Özçelik, V. O.; Durgun, Engin; Çıracı, Salim (Royal Society of Chemistry, 2019)
      Two-dimensional (2D) antimonene, bismuthene, and their binary compound 2D BiSb possess high spin–orbit coupling (SOC) and potential topological insulator properties upon engineering their structural and chemical properties. ...
    • Superlubricity through graphene multilayers between Ni (111) surfaces 

      Cahangirov, S.; Çıracı, Salim; Özçelik, V. O. (American Physical Society, 2013)
      A single graphene layer placed between two parallel Ni(111) surfaces screens the strong attractive force and results in a significant reduction of adhesion and sliding friction. When two graphene layers are inserted, each ...
    • Two-dimensional pnictogens: a review of recent progresses and future research directions 

      Ersan, Fatih; Keçik, Deniz; Özçelik, V. O.; Kadıoğlu, Yelda; Üzengi-Aktürk, O.; Durgun, Engin; Aktürk, Ethem; Çıracı, Salim (American Institute of Physics, 2019)
      Soon after the synthesis of two-dimensional (2D) ultrathin black phosphorus and fabrication of field effect transistors thereof, theoretical studies have predicted that other group-VA elements (or pnictogens), N, As, Sb, ...