Download or read book Scanning Tunneling Microscopy Study of Defects and Devices in Topological Materials written by Michael Gottschalk and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Topological phases in condensed matter systems have received tremendous interest in the past two decades. Theoretical work has shown how topological invariants can be calculated from the band structures in a wide range of insulating systems that contain an energy gap. Broadly speaking, these topological invariants are quantities that are invariant under continuous deformation so long as specific symmetries hold and the energy gap stays open. What separates topological states of matter from traditional phases is the concept of bulk-boundary correspondence. The topology of the vacuum is trivial, so if the bulk of a material is topologically non-trivial, the energy gap must close at the boundary between the two. This creates conducting states at the boundaries, or edges, of the material; the conducting states within the gap have specific properties. Strong, 3Dtopological insulators, such as Bi2Se3 , are materials that are insulating in the bulk with conducting surface states due to bulk-boundary correspondence. The surface states are topologically protected from local perturbations and feature a linear dispersion relation, known as the Dirac cone. Bi2Se3is one of the most widely studied topological insulators due to the relative simplicity of its band structure with a single Dirac cone. In this work, I study the effects of N2 gas on the surface states of Bi2Se3 , which appears to p-type dope the density of states spectra measured with a scanning tunneling microscope. Topological superconductors have also garnered great interest for their potential applications in topological quantum computing. The second half of this dissertation is focused on describing, fabricating, and measuring a potential platform for a possible topological superconducting state known as a Majorana zero mode. These devices feature Nb sputtered onBi2Se3 that is patterned into Josephson junctions with e-beam lithography techniques.
Download or read book Scanning Tunneling Microscopy Study on Superlattice Topological Materials written by 張昱 and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scanning Tunneling Microscopy II written by Roland Wiesendanger and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scanning Tunneling Microscopy II, like its predecessor, presents detailed and comprehensive accounts of the basic principles and the broad range of applications of STM and related scanning probe techniques. The applications discussed in this volume come predominantly from the fields of electrochemistry and biology. In contrast to those in STM I, these studies may be performed in air and in liquids. The extensions of the basic technique to map other interactions are described in chapters on scanning force microscopy, magnetic force microscopy, and scanning near-field optical microscopy, together with a survey of other related techniques. Also discussed here is the use of a scanning proximal probe for surface modification. Together, the two volumes give a comprehensive account of experimental aspects of STM and provide essential reading and reference material. In this second edition the text has been updated and new methods are discussed.
Download or read book Scanning Tunneling Microscopy written by H. Neddermeyer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: The publication entitled "Surface Studies by Scanning Tunneling Mi Rl croscopy" by Binnig, Rohrer, Gerber and Weibel of the IBM Research Lab oratory in Riischlikon in 1982 immediately raised considerable interest in the sur face science community. It was demonstrated in Reference R1 that images from atomic structures of surfaces like individual steps could be obtained simply by scanning the surface with a sharp metal tip, which was kept in a constant distance of approximately 10 A from the sample surface. The distance control in scanning tunneling microscopy (STM) was realized by a feedback circuit, where the electri cal tunneling current through the potential barrier between tip and sample is used for regulating the tip position with a piezoelectric xyz-system. A similar experi mental approach has already been described by Young et al. for the determination l of the macroscopic roughness of a surface. A number of experimental difficulties had to be solved by the IBM group until this conceptual simple microscopic method could be applied successfully with atomic resolution. Firstly, distance and scanning control of the tip have to be operated with sufficient precision to be sensitive to atomic structures. Secondly, sample holder and tunneling unit have to be designed in such a way that external vibrations do not influence the sample-tip distance and that thermal or other drift effects become small enough during measurement of one image.
Download or read book Scanning Tunneling Microscopy in Surface Science Nanoscience and Catalysis written by Michael Bowker and published by John Wiley & Sons. This book was released on 2009-11-11 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, top international authors in the field of STM and surface science present first-class contributions on this hot topic, bringing the reader up to date with the latest developments in this rapidly advancing field. The focus is on the nanoscale, particularly in relation to catalysis, involving developments in our understanding of the nature of the surfaces of oxides and nanoparticulate materials, as well as adsorption, and includes in-situ studies of catalysis on such model materials. Of high interest to practitioners of surface science, nanoscience, STM and catalysis.
Download or read book Scanning Tunneling Microscopy Studies of Defects in Semiconductors written by Anne Laura Benjamin and published by . This book was released on 2018 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis addresses scanning tunneling microscopy (STM) studies of metal defects in GaAs(110). Single-atom defects are useful for their potential applications in developing nano-scale miniaturized or new types of optical, magnetic, and electronic devices, as well as expanding our understanding of atomic-scale interactions. STM is used to measure physical and electronic properties of surface and near-surface materials with atomic resolution, but affects the properties of defects being studied.
Download or read book Scanning Tunneling Microscopy I written by Hans-Joachim Güntherodt and published by Springer Science & Business Media. This book was released on 2013-03-13 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the first edition of "Scanning 'funneling Microscopy I" has been pub lished, considerable progress has been made in the application of STM to the various classes of materials treated in this volume, most notably in the field of adsorbates and molecular systems. An update of the most recent develop ments will be given in an additional Chapter 9. The editors would like to thank all the contributors who have supplied up dating material, and those who have provided us with suggestions for further improvements. We also thank Springer-Verlag for the decision to publish this second edition in paperback, thereby making this book affordable for an even wider circle of readers. Hamburg, July 1994 R. Wiesendanger Preface to the First Edition Since its invention in 1981 by G. Binnig, H. Rohrer and coworkers at the IBM Zurich Research Laboratory, scanning tunneling microscopy (STM) has devel oped into an invaluable surface analytical technique allowing the investigation of real-space surface structures at the atomic level. The conceptual simplicity of the STM technique is startling: bringing a sharp needle to within a few Angstroms of the surface of a conducting sample and using the tunneling cur rent, which flows on application of a bias voltage, to sense the atomic and elec tronic surface structure with atomic resolution! Prior to 1981 considerable scepticism existed as to the practicability of this approach.
Download or read book Scanning Tunneling Microscopy and Its Application written by Chunli Bai and published by Springer Science & Business Media. This book was released on 2000-08-10 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a unified view of the rapidly growing field of scanning tunneling microscopy and its many derivatives. After examining novel scanning-probe techniques and the instrumentation and methods, the book provides detailed accounts of STM applications. It examines limitations of the present-day investigations and provides insight into further trends. "I strongly recommend that Professor Bai's book be a part of any library that serves surface scientists, biochemists, biophysicists, material scientists, and students of any science or engineering field...There is no doubt that this is one of the better (most thoughtful) texts." Journal of the American Chemical Society (Review of 1/e)
Download or read book Scanning Probe Microscopy and Spectroscopy written by Roland Wiesendanger and published by Cambridge University Press. This book was released on 1994-09-29 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt: The investigation and manipulation of matter on the atomic scale have been revolutionised by scanning tunnelling microscopy and related scanning probe techniques. This book is the first to provide a clear and comprehensive introduction to this subject. Beginning with the theoretical background of scanning tunnelling microscopy, the design and instrumentation of practical STM and associated systems are described in detail, as are the applications of these techniques in fields such as condensed matter physics, chemistry, biology, and nanotechnology. Containing 350 illustrations, and over 1200 references, this unique book represents an ideal introduction to the subject for final-year undergraduates in physics or materials science. It will also be invaluable to graduate students and researchers in any branch of science where scanning probe techniques are used.
Download or read book Scanning Tunneling Microscopy II written by Roland Wiesendanger and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scanning Tunneling Microscopy II, like its predecessor, presents detailed and comprehensive accounts of the basic principles and broad range of applications of STM and related scanning probe techniques. The applications discussed in this volume come predominantly from the fields of electrochemistry and biology. In contrast to those described in Vol. I, these sudies may be performed in air and in liquids. The extensions of the basic technique to map other interactions are described inchapters on scanning force microscopy, magnetic force microscopy, scanning near-field optical microscopy, together with a survey of other related techniques. Also described here is the use of a scanning proximal probe for surface modification. Togehter, the two volumes give a comprehensive account of experimental aspcets of STM. They provide essentialreading and reference material for all students and researchers involvedin this field.
Download or read book Scanning Probe Microscopy Characterization Nanofabrication and Device Application of Functional Materials written by Paula Maria Vilarinho and published by Springer Science & Business Media. This book was released on with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scanning Tunneling Microscopy of Two dimensional Materials written by Grady A. Gambrel and published by . This book was released on 2017 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-dimensional materials are of fundamental and practical interest due to the unique properties they exhibit. As they are only one layer or one atom thick, their physical and electronic properties are sensitive to their local environment, and may be manipulated by engineering variations within the materials. Incorporating these materials into electronic devices requires that their interactions are well understood so that they behave as predicted. For this reason, the study of defects, likely contaminants, and engineered structures is worthwhile. The scanning tunneling microscope is of particular use in such experiments as it can be used to characterize the atomic structure and locally measure the electronic properties of samples. Graphene islands were grown on Cu(111) in ultrahigh vacuum to study graphene/copper interactions with minimal surface adsorbates. Using in situ low-temperature scanning tunneling microscopy (STM), both the physical and electronic structure were measured with atomic spatial resolution and compared with those of clean copper regions. These measurements indicate a decrease in the work function relative to clean Cu(111) and reduced coupling of surface electronic states to the bulk. Other measurements find that both the band edge and effective mass of Shockley surface state electrons are infuenced by the graphene layer. Similarly, single-layer germanene was grown on and measured on Cu(111). A competing alloy process which forms Cu2Ge restricts notable germanene coverage to a substrate temperature range between 40 degrees and 150 degrees Celsius. Atomic resolution imaging and tunneling spectroscopy are used to distinguish germanene and Cu2Ge regions, and probe the interaction of both with the Cu(111) substrate. Germanene was found to be weakly coupled to the Cu(111), maintaining an incommensurate 3.8 Angstrom lattice but lack any clear signatures of the Dirac point. In contrast, a 4.4 Angstrom lattice is observed on Cu2Ge that is commensurate with a v3 x v3 R30 reconstruction of Cu(111), and distinct unoccupied electronic states are observed well above the sample Fermi level.
Download or read book Scanning Tunneling Microscopy I written by Hans-Joachim Güntherodt and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scanning Tunneling Microscopy I provides a unique introduction to a novel and fascinating technique that produces beautiful images of nature on an atomic scale. It is the first of three volumes that together offer a comprehensive treatment of scanning tunneling microscopy, its diverse applications, and its theoretical treatment. In this volume the reader will find a detailed description of the technique itself and of its applications to metals, semiconductors, layered materials, adsorbed molecules and superconductors. In addition to the many representative results reviewed, extensive references to original work will help to make accessible the vast body of knowledge already accumulated in this field.
Download or read book Scanning Tunneling Microscopy and Spectroscopy of Topological Materials with Broken Symmetry written by Kane Lee Scipioni and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scanning Tunneling Microscope and Atomic Force Microscopy written by Suchit Sharma and published by GRIN Verlag. This book was released on 2017-12-05 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Literature Review from the year 2015 in the subject Engineering - General, Indian Institute of Technology, Delhi, course: Mineral Engineering, language: English, abstract: Atomic-scale resolution is needed to study the arrangement of atoms in materials and advancing their understanding. Since the seventeenth-century optical microscopes using visible light as illumination source have led our quest to observe microscopic species but the resolution attainable reached physical limits due to the much longer wavelength of visible light. After the discovery of wave nature associated with particle bodies, a new channel of thought opened considering much shorter wavelength of particles and their special properties when interacting with the sample under observation. These particles i.e. electrons, neutrons and ions were developed in different techniques and were used as illumination sources. Herein, the development of scanning tunneling microscopy which used electrons to uncover irregularities in the arrangement of atoms in thin materials via the quantum mechanical phenomenon of electron tunneling became a sensational invention. Atomic Force Microscopy (AFM) is a development over STM which relied on measuring the forces of contact between the sample and a scanning probe which overcame the earlier technique only allowing conductors or pretreated surfaces for conducting to be observed. Since measuring contact forces between materials is a more fundamental approach that is equally but more sensitive than measuring tunneling current flowing between them, atomic force microscopy has been able to image insulators as well as semiconductors and conductors with atomic resolution by substituting tunneling current with an atomic contact force sensing arrangement, a delicate cantilever, which can image conductors and insulators alike via mechanical "touch" while running over surface atoms of the sample. AFM has seen a massive proliferation in hobbyist’s lab in form of ambient-condition scanning environment as opposed to an ultra-high vacuum of sophisticated labs and self-assembled instrumentations. The success of ATM as a cost-effective imaging tool with dramatically increased ease of conceptual understanding and use particularly with the assistance of significant computing power in the form of personal computers which offsets the computational difficulty of resolving experimental information which makes up for physical simplicity of instrument design has seen its proliferation to numerous labs in universities and technology companies worldwide.
Download or read book Introduction to Scanning Tunneling Microscopy written by C. Julian Chen and published by Oxford University Press. This book was released on 1993-05-20 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to its nondestructive imaging power, scanning tunneling microscopy has found major applications in the fields of physics, chemistry, engineering, and materials science. This book provides a comprehensive treatment of scanning tunneling and atomic force microscopy, with full coverage of the imaging mechanism, instrumentation, and sample applications. The work is the first single-author reference on STM and presents much valuable information previously available only as proceedings or collections of review articles. It contains a 32-page section of remarkable STM images, and is organized as a self-contained work, with all mathematical derivations fully detailed. As a source of background material and current data, the book will be an invaluable resource for all scientists, engineers, and technicians using the imaging abilities of STM and AFM. It may also be used as a textbook in senior-year and graduate level STM courses, and as a supplementary text in surface science, solid-state physics, materials science, microscopy, and quantum mechanics.
Download or read book Advances in Scanning Probe Microscopy written by T. Sakurai and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: There have been many books published on scanning tunneling microscopy (STM), atomic force microscopy (AFM) and related subjects since Dr. Cerd Binnig and Dr. Heinrich Rohrer invented STM in 1982 and AFM in 1986 at IBM Research Center in Zurich, Switzerland. These two techniques, STM and AFM, now form the core of what has come to be called the 'scanning probe microscopy (SPM)' family. SPM is not just the most powerful microscope for scientists to image atoms on surfaces, but is also becoming an indispensable tool for manipulating atoms and molecules to construct man-made materials and devices. Its impact has been felt in various fields, from surface physics and chemistry to nano-mechanics, nano-electronics and medical science. Its influence will surely extend further as the years go by, beyond the reach of our present imagination, and new research applications will continue to emerge. This book, therefore, is not intended to be a comprehensive review or textbook on SPM. Its aim is to cover only a selected part of the active re search fields of SPM and related topics in which I have been directly involved over the years. These include the basic principles of STM and AFM, and their applications to fullerene film growth, SiC surface reconstructions, MBE (molecular beam epitaxy) growth of CaAs, atomic scale manipulation of Si surfaces and meso scopic work function.
