Molecular dynamics investigation of Moire Patterns in double-layer graphene

Download
index.pdf
2012
Sökmen, Gökçe
Show full item record
268
views
147
downloads
Before Moire patterns are discovered in graphene, graphene was assumed to be found in only the rhombohedral form in nature. After transfer of graphene layer over another substrate was achieved by Andre Geim and Konstantin Novoselov, studies on graphene gained momentum. Following this, moire paterns were observed by scanning tunelling microscopy (STM) and high resolution transmision electron microscopy (HR-TEM). However, stability of these structures are still unknown. In this thesis, for the first time in literature, molecular dynamics of double layer graphene based Moire patterns are investigated as a result of the rotation of two graphene layers with LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) which has a GNU general public license. To model the two graphene layers, hexagonal graphene layers are generated by home writen Octave code. Then, periodicity condition for the Moire patterns are derived in chapter 2 according to rotation of graphene layers around their central axis, perpendicular to the layers. Then these layers with di fferent angles or temperature or size are simulated by LAMMPS. There are 4 kind of molecular dynamics simulations studied according to modeled flakes. These are grouped under the name of ’Experiment #’ according to the modeling structure. Experiment-1 simulates double layer hexagonal flakes of graphene at a temperature of 0.1K. Experiment-2 simulates periodic moire patterns under periodic boundary conditions and represents the infinitely large graphene layers at 10K. Experiment 3 is di erent version of the experiment 1 but at higher temperature (10K). Finally, experiment 4 is modeled to show the behaviour of the graphene flake on a growth or attached region. The atoms around the flakes are modeled as a rigid body and constructs some stress on the graphene flakes.
Graphene., Polycyclic aromatic hydrocarbons., Moiré method., Photogrammetry., Molecular dynamics.
http://etd.lib.metu.edu.tr/upload/12614751/index.pdf
https://hdl.handle.net/11511/21947
Graduate School of Natural and Applied Sciences, Thesis

Suggestions

Investigation of the structural properties of silicene nanoribbons by molecular dynamics simulations
İnce, Alper; Erkoç, Şakir; Aydınol, Mehmet Kadri; Department of Micro and Nanotechnology (2012)
With the emergence of nanotechnology, mankind has obtained the capability to manipulate materials at nanoscale and this led to the invention of a new group of novel materials like carbon nanotubes, graphene and quantum nanodots. Silicene nanoribbons (SiNRs) are one of the newest members of this nanomaterial family which has been synthesized very recently by deposition on silver substrates. A SiNR sheet is made up of a layer of two dimensional honeycomb structure solely composed of silicon atoms. In this the...
Chemical Vapour Deposition of Graphene with Re useable Pt and Cu substrates for Flexible Electronics
Karamat, Shumaıla; Sonusen, Selda; Çelik, Ümit; Uysallı, Yiğit; Oral, Ahmet (null; 2015-03-06)
Graphene has gained the attention of scientific world due to its outstanding physical properties. The future demand of flexible electronics such as solar cells, light emitting diodes, photo-detectors and touch screen technology requires more exploration of graphene properties on flexible substrates. The most interesting application of graphene is in organic light emitting diodes (OLED) where efforts are in progress to replace brittle indium tin oxide (ITO) electrode with a flexible graphene electrode becaus...
Phonon mean free path in few layer, two-dimensional hexagonal structures
Gholivand, Hamed; Dönmezer, Nazlı; Department of Mechanical Engineering (2017)
Two-dimensional materials such as graphene and few layer hexagonal Boron Nitride (h-BN) have been the center of attention in the last decade. These materials provide anisotropic and exclusive properties making them ideal candidates for the modern electronic and optoelectronic applications. With the enhancements in fabrication techniques and the ability to separate thin layers their popularity is continuously increasing. Understanding the thermal properties of these materials is necessary to make better devi...
Density functional theory and molecular dynamics simulations of carbon nanotubes, polyetheretherketone and their interfaces
Toraman, Gözdenur; Toffoli, Hande; Gürses, Ercan; Department of Physics (2018)
Carbon nanotubes are allotropes of carbon with a cylindrical nanostructure. A nanotube can roughly be described as a rolled-up graphene sheet, which is a two dimensional hexagonal arrangement of carbon atoms, often referred to as a honeycomb lattice. Carbon nanotubes, much like their parent material graphene, are characterized by high strength, high Young modulus, durability and tunable electronic behavior. As a result of these superior properties, CNTs have been used in diverse technologically relevant app...
Structural Vibration Analysis of Single Walled Carbon Nanotubes with Atom Vacancies
Dogan, Ibrahim Onur; Yazıcıoğlu, Yiğit (2014-11-01)
Recent investigations in nanotechnology show that carbon nanotubes have significant mechanical, electrical and optical properties. Interactions between those are also promising in both research and industrial fields. Those unique characteristics are mainly due to the atomistic structure of carbon nanotubes. In this paper, the structural effects of vacant atoms on single walled carbon nanotubes are investigated using matrix stiffness method. In order to use this technique, a linkage between structural mechan...
Citation Formats
G. Sökmen, “Molecular dynamics investigation of Moire Patterns in double-layer graphene,” M.S. - Master of Science, Middle East Technical University, 2012.
METU IIS - Integrated Information Service open@metu.edu.tr