Author
Sarah A. Burke
Other affiliations: Dalhousie University, McGill University, University of California, Berkeley
Bio: Sarah A. Burke is an academic researcher from University of British Columbia. The author has contributed to research in topics: Scanning tunneling microscope & Scanning tunneling spectroscopy. The author has an hindex of 21, co-authored 51 publications receiving 2450 citations. Previous affiliations of Sarah A. Burke include Dalhousie University & McGill University.
Papers published on a yearly basis
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TL;DR: Experimental spectroscopic measurements by scanning tunneling microscopy of highly strained nanobubbles that form when graphene is grown on a platinum surface open the door to both the study of charge carriers in previously inaccessible high magnetic field regimes and deliberate mechanical control over electronic structure in graphene or so-called “strain engineering.”
Abstract: Recent theoretical proposals suggest that strain can be used to engineer graphene electronic states through the creation of a pseudo-magnetic field. This effect is unique to graphene because of its massless Dirac fermion-like band structure and particular lattice symmetry (C3v). Here, we present experimental spectroscopic measurements by scanning tunneling microscopy of highly strained nanobubbles that form when graphene is grown on a platinum (111) surface. The nanobubbles exhibit Landau levels that form in the presence of strain-induced pseudo-magnetic fields greater than 300 tesla. This demonstration of enormous pseudo-magnetic fields opens the door to both the study of charge carriers in previously inaccessible high magnetic field regimes and deliberate mechanical control over electronic structure in graphene or so-called "strain engineering."
1,343 citations
TL;DR: In this article, the adhesion forces of Si3N4 tips to the surfaces of Gram-negative bacterial strains possessing different lipopolysacharides (LPS) (i.e., Pseudomonas aeruginosa PAO1 and its isogenic mutants) was investigated without the use of surface modifying or bonding agents to adhere cells to the filter.
187 citations
TL;DR: Simultaneous molecular and atomic resolution on the C60 and KBr surfaces, respectively, was obtained revealing a coincident 8x3 superstructure and a 21+/-3 pm apparent height difference was observed in atomic force microscopy topographies between some first layer molecules.
Abstract: Noncontact atomic force microscopy has been applied to the prototypical molecule-insulator system C60 on KBr to study nucleation and submonolayer growth. Overview images reveal an island growth mode with unusual branching structures. Simultaneous molecular and atomic resolution on the C60 and KBr surfaces, respectively, was obtained revealing a coincident 8x3 superstructure. Also, a 21+/-3 pm apparent height difference was observed in atomic force microscopy topographies between some first layer molecules. One of the initial nucleation sites of the C60 islands was determined by observation of loosely bound molecules at kink sites in monatomic KBr steps, in conjunction with the observation that islands form preferentially at step edges.
96 citations
TL;DR: Submonolayer coverages of the molecule 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) deposited on NaCl(001) surfaces were imaged with high resolution noncontact-atomic force microscopy to show the p3x3 epitaxy to be incompatible with a multilayer crystal of PTCDA.
Abstract: The nanofibrous film of polyurethane (PU) with aligned topography was fabricated by electrospinning for human umbilical vein endothelial cells(HUVEC) growth. The morphology of nanofibrous film was observed and characterized by scanning electron microscopy(SEM). The cells growth behavior including proliferation, cytoskeleton formation of actin, tublin and vinculin, and tissue factor(TF) release was investigated via cell viability assay, confocal observation and TF assay. The average diameter of the generated fiber was around 300-500 nm. The experimental results indicate that the aligned nanofibrous film of PU exhibited promotional influence on the cell proliferation. It was also observed that the film possessed an advantage of supporting HUVEC migrating and aggregating along the axis of the aligned nanofibers, which is one of the important functions in the process of endothelium regeneration. It was also demonstrated that the endothelial cells growing on the film expressed non-thrombogenic phenotype with low tissue factor released. These results indicate the favorable interactions between ECs and the film, implying that the aligned nanofibrous film of PU has a promising potential for vascular engineering.
89 citations
TL;DR: The origins of different growth modes and the thickness dependent interactions which give rise to dewetting are discussed in terms of surface energies and the disjoining pressure, and examples of molecule-on-insulator systems which undergo deWetting are described in some detail.
Abstract: Recent attention given to the growth and morphology of organic thin films with regard to organic electronics has led to the observation of dewetting (a transition from layer(s) to islands) of molecular deposits in many of these systems. Dewetting is a much studied phenomenon in the formation of polymer and liquid films, but its observation in thin films of the 'small' molecules typical of organic electronics requires additional consideration of the structure of the interface between the molecular film and the substrate. This review covers some key concepts related to dewetting and molecular film growth. In particular, the origins of different growth modes and the thickness dependent interactions which give rise to dewetting are discussed in terms of surface energies and the disjoining pressure. Characteristics of molecular systems which may lead to these conditions, including the formation of metastable interface structures and commensurate–incommensurate phase transitions, are also discussed. Brief descriptions of some experimental techniques which have been used to study molecular dewetting are given as well. Examples of molecule-on-insulator systems which undergo dewetting are described in some detail, specifically perylene derivatives on alkali halides, C60 on alkali halides, and the technologically important system of pentacene on SiO2. These examples point to some possible predicting factors for the occurrence of dewetting, most importantly the formation of an interface layer which differs from the bulk crystal structure.
84 citations
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TL;DR: The atomic force microscope (AFM) is not only used to image the topography of solid surfaces at high resolution but also to measure force-versus-distance curves as discussed by the authors, which provide valuable information on local material properties such as elasticity, hardness, Hamaker constant, adhesion and surface charge densities.
3,281 citations
University of Cambridge1, Istituto Italiano di Tecnologia2, Lancaster University3, University of Manchester4, Catalan Institution for Research and Advanced Studies5, Technical University of Denmark6, Nokia7, University of Trento8, Queen Mary University of London9, fondazione bruno kessler10, Technische Universität München11, Polytechnic University of Milan12, Centre national de la recherche scientifique13, University of Trieste14, University of Ioannina15, University of Geneva16, Trinity College, Dublin17, Texas Instruments18, University of Paris19, Spanish National Research Council20, Leiden University21, Delft University of Technology22, University of Patras23, École Normale Supérieure24, Radboud University Nijmegen25, Nest Labs26, Airbus UK27, Seoul National University28, Yonsei University29, University of Oxford30, Chalmers University of Technology31, University of Groningen32, STMicroelectronics33, Chemnitz University of Technology34, Max Planck Society35, Aalto University36
TL;DR: An overview of the key aspects of graphene and related materials, ranging from fundamental research challenges to a variety of applications in a large number of sectors, highlighting the steps necessary to take GRMs from a state of raw potential to a point where they might revolutionize multiple industries are provided.
Abstract: We present the science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems, targeting an evolution in technology, that might lead to impacts and benefits reaching into most areas of society. This roadmap was developed within the framework of the European Graphene Flagship and outlines the main targets and research areas as best understood at the start of this ambitious project. We provide an overview of the key aspects of graphene and related materials (GRMs), ranging from fundamental research challenges to a variety of applications in a large number of sectors, highlighting the steps necessary to take GRMs from a state of raw potential to a point where they might revolutionize multiple industries. We also define an extensive list of acronyms in an effort to standardize the nomenclature in this emerging field.
2,560 citations
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TL;DR: In this paper, the authors review the field emerging at the intersection of graphene physics and plasmonics and review the applications of graphene-based plasmons for optical devices with extremely high speed, low driving voltage, low power consumption and compact sizes.
Abstract: Two rich and vibrant fields of investigation, graphene physics and plasmonics, strongly overlap Not only does graphene possess intrinsic plasmons that are tunable and adjustable, but a combination of graphene with noble-metal nanostructures promises a variety of exciting applications for conventional plasmonics The versatility of graphene means that graphene-based plasmonics may enable the manufacture of novel optical devices working in different frequency ranges, from terahertz to the visible, with extremely high speed, low driving voltage, low power consumption and compact sizes Here we review the field emerging at the intersection of graphene physics and plasmonics
2,475 citations