Mattias L N Palsgaard, Center for Nanostructured Graphene, Dept. of Micro- and Nanotechnology, Technical University of Denmark, Ørsted Plads, Bldg. 345E, DK-2800 Kongens Lyngby, Denmark. 
 
Inelastic tunneling into a suspended graphene sheet is investigated, using Density Functional Theory combined with the Non-Equilibrium Green’s Function formalism. Electronic coupling to the vibrations in graphene is included, with a Lowest Order Expansion of the Self-Consistent Born Approximation.The results show a gap in tunneling conductance unique to graphene and caused by inelastic effects. The physics of this phenomenon is captured approximately by the method used. The gap is independent on change in the gate voltage and increase of the tunneling distance. The stability of the gap feature, with respect to various modifications of the pristine graphene lattice, is tested.Imperfections in the graphene lattice are found to quench the gap locally, leading to artificial protrusions in STM topography images. Additionally, inelastic fingerprints are found for a range of different imperfections ranging from structural defects to covalently bonded adsorbates and edges. 
 
Mattias Palsgaard graduated from the Technical University of Denmark (DTU) in March 2014 as a Civil Engineer in Physics and Nanotechnology.
He has since then been working as a Research Assistant in the group of Assoc. Prof. Mads Brandbyge at DTU. His main focus is on first principles calculation of Scanning Tunneling Microscopy measurements on grapheme including electron coupling to vibrations of the crystal lattice. In July of 2014, he received the Best Poster Award at the Quantumhagen Conference in Copenhagen.

Vijayshankar Asokan, Dorte Nørgaard Madsen, Department of Physics and Technology, University of Bergen, Norway, 5007 

CB is a well-known type of amorphous carbon which exists in the form of aggregated spheres. It lies in the category of non-graphitizable carbon. Many bent and faceted layer planes and few closed-shell structures could be obtained when CB was treated at high temperature and however carbon undergoes structural transformation when it comes in contact with metal catalysts at high temperature. The degree of transformation and morphology of resulting nanostructure depends on many factors which this project takes into consideration and studied. In this work, an easy, economical and single-step process for the transformation of CB into a large quantities of metal-encapsulated multi-walled carbon nanobeads (MWNB) and multi-walled carbon nanotubes (MWNT) is carried out. Further, this works studied the possibilities of transformation CB into a nano-onions and nanofibers using microwave energy with and without use of any metal catalysts respectively. Process of transformation of CB particles is studied with respect to temperature, inert gas, metal catalysts (Ni, Fe) and their weight ratios with respect to CB taken during experiment. Electron microscopes (Scanning, transmission and high-resolution transmission), Raman spectroscopy, Thermal gravimetry analysis, X-ray diffraction methods are used for the characterization of these samples. 

Vijayshankar Asokan is currently a PhD research student at University of Bergen, Norway. He is primarily interested in the synthesis and characterization of nanomaterials, thin films. He received his B.Sc. degree in Applied Sciences from Coimbatore Institute of Technology, India (2004), MSc degree in Materials Science from PSG College of Technology (2006), India. He joined University of Bergen in May 2008 as PhD research fellow and his research area includes synthesis of carbon nanotubes and surface functionalization of nano carbon for fuel cell applications and has expertise in the operations of thin film systems (thermal evaporation, sputtering, chemical vapor deposition and electron beam evaporation) and different material characterization methods includes Scanning electron microscope, Transmission electron microscope, High-resolution transmission electron microscope, Particle size analyzer, Zeta potential measurements, surface area analyzer, Raman and UV/IR Spectroscopy, Electrochemical impedance spectroscopy.

Sanjay Behura and Omkar Jani
Gujarat Energy Research and Management Institute, Gandhinagar 382007, Gujarat, India 

The excellent characteristics of graphene (optical and electrical) make it a better choice for photovoltaic applications. In this work, graphene has been synthesized by chemical oxidation of graphite (modified Hummers method) and subsequently its reduction to graphene. Furthermore reduced graphene oxide has been spin-coated on crystalline silicon (1 0 0) of both n and p-types to make the heterojunction solar cells. A through material and device characterizations have been made to understand the junction characteristics.

Sanjay Behura is presently working as Junior Scientist at Gujarat Energy Research and Management Institute in Gandhinagar, India. He has submitted his Ph.D. thesis in Materials Physics to Pandit Deendayal Petroleum University, Gandhinagar based on his research work at the University of Saskatchewan, Canada under Commonwealth Graduate Scholarship (2011-12). He is interested in junction characteristics of graphene-on-semiconductors for photovoltaic applications. He has published 17 international peer-reviewed papers in SCI Journals and refereed conference proceedings. He has received various academic awards and scholarships such as: Best Science Graduate Award (2006), IIT-GATE in Physics (2009), Joint CSIR-UGC NET in Physical Sciences (June 2009), Canada Commonwealth Graduate Scholarship (2011-12), Best Poster Prize in WRETC (2013) and DST Award of International Travel Support Scheme for Young Scientists (2014).

Stephen R. Power and Antti-Pekka Jauho, Centre for Nanostructured Graphene (CNG), DTU Nanotech, Technical University of Denmark

Nanostructuring of graphene is in part motivated by the requirement to open a gap in the electronic band structure of graphene. Periodically perforated graphene sheets (antidot lattices) are predicted to have such a gap.
These systems have been investigated experimentally and theoretically with a view towards application in transistor or waveguiding devices. The desired properties have been predicted for atomically precise systems, but fabrication introduces significant disorder in the shape, position and edge configurations of individual antidots.
We calculate the electronic transport properties of a range of graphene antidot devices to determine the effect of such disorders on their performance. Modest geometric disorder has a detrimental effect on the performance of devices containing small, tightly packed antidots which show optimal performance for pristine lattices.
Larger antidots, meanwhile, display a range of effects strongly dependent on their edge geometry.
The transport gap of antidot systems with armchair edges is far more robust than those composed from antidots with zigzag or mixed edges. Waveguiding devices are also investigated, where the role of disorder is different and can enhance performance by extending the energy range over which waveguiding behaviour is observed. Preprint: arxiv.org/abs/1407.0311

Stephen Power is currently a post doctoral researcher in the Center for Nanostructured Graphene (CNG), based at the Department of Micro- and Nanotechnology (DTU Nanotech), Technical University of Denmark. He is primarily interested in the electronic, magnetic and transport properties of graphene-based systems. He received his B.A. in Theoretical Physics (2007) and Ph.D (2012) from Trinity College Dublin.

Izabela Kondratowicz, Nanotechnology, Faculty of Applied Physics and Mathematics , Gdansk University of Technology, Narutowicza 11/12, 80-233, Gdańsk, Poland
Kamila Żelechowska, Department of Physics of Electronic Phenomena, Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-233, Gdańsk, Poland 

The growing demand for efficient and safe methods to store and convert energy has inspired scientists to look for the new active materials for electrodes. Graphene obtained during the hydrothermal reduction of graphene oxide has a three dimensional, highly porous aerogel structure and thus has shown a great potential as an electrode material. In our work, we focused on the synthesis of graphene aerogels under different conditions. First graphene oxide (GO) was prepared using a well-known Hummers method and its modifications. The water dispersion was then sonicated and in the next step ascorbic acid was added to reduce graphene oxide to the reduced graphene oxide (rGO) in a form of the hydrogel. After the drying process graphene aerogel (GA) was obtained. We characterized these structures using infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and cyclic voltammetry. As-obtained aerogels can be used as materials for lithium-ion batteries, supercapacitors, solar cells, fuel and biofuel cells. 

Izabela Kondratowicz is a graduate of the Gdansk University of Technology where she is going to start her PhD studies. She received her B.Eng. degree in Technical Physics (2012) and a M.Sc. in Nanotechnology (2014) from Gdansk University of Technology in Poland. She was an exchange student at the Technical University of Denmark. She is primarily interested in the applications of nanotechnology in biomedical sciences, the properties of carbon nanomaterials and nanofabrication techniques. Her current work focuses on graphene and its application in biofuel cells.

T. Markussen, QuantumWise A/S, Lersø Parkallé 107, DK-2100 Copenhagen, Denmark 

We present a conceptually simple method for calculating phonon-limited mobilities. By combining classical molecular dynamics simulations with (elastic) Landauer transmission calculations using a tight-binding model, we compute a temperature dependent scattering resistance from which we can extract the mobility. Despite the simplicity of the approach, we successfully reproduce experimental room temperature mobilities for different semiconductors and graphene spanning two orders of magnitude. Likewise we accurately reproduce an almost two orders of magnitude modulation of the silicon electron mobility, when increasing the temperature from 50 K to 300 K. The good agreement between our numerically easy method and experimental mobilities is promising for further studies of electron-phonon interactions in non-periodic device systems including 1D and 2D-confined structures, where experimental data are less available.

Troels Markussen is scientific specialist at QuantumWise A/S. He received his Ph.D. in 2009 from the Technical University of Denmark (DTU), Dept. of Micro and Nanotechnology. After that he was applied as postdoc at the Dept. of Physics, also at DTU. In 2011 he received an individual postdoc scholarship Founded by the Danish Council for Independent Research, FTP, through the Sapere-Aude Young Elite Researchers program. His research interest concerns atomic-scale simulations of electron- and phonon transport in nanowires and molecular junctions. Particular interest are thermoelectric energy conversion and quantum interference effects.