Download or read book Reshaping of Dirac Cones in Topological Insulators and Graphene written by Álvaro Díaz Fernández and published by Springer Nature. This book was released on 2020-12-09 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dirac cones are ubiquitous to non-trivial quantum matter and are expected to boost and reshape the field of modern electronics. Particularly relevant examples where these cones arise are topological insulators and graphene. From a fundamental perspective, this thesis proposes schemes towards modifying basic properties of these cones in the aforementioned materials. The thesis begins with a brief historical introduction which is followed by an extensive chapter that endows the reader with the basic tools of symmetry and topology needed to understand the remaining text. The subsequent four chapters are devoted to the reshaping of Dirac cones by external fields and delta doping. At all times, the ideas discussed in the second chapter are always a guiding principle to understand the phenomena discussed in those four chapters. As a result, the thesis is cohesive and represents a major advance in our understanding of the physics of Dirac materials.
Download or read book Reshaping of Dirac Cones in Topological Insulators and Graphene written by Álvaro Díaz Fernández and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dirac cones are ubiquitous to non-trivial quantum matter and are expected to boost and reshape the field of modern electronics. Particularly relevant examples where these cones arise are topological insulators and graphene. From a fundamental perspective, this thesis proposes schemes towards modifying basic properties of these cones in the aforementioned materials. The thesis begins with a brief historical introduction which is followed by an extensive chapter that endows the reader with the basic tools of symmetry and topology needed to understand the remaining text. The subsequent four chapters are devoted to the reshaping of Dirac cones by external fields and delta doping. At all times, the ideas discussed in the second chapter are always a guiding principle to understand the phenomena discussed in those four chapters. As a result, the thesis is cohesive and represents a major advance in our understanding of the physics of Dirac materials.
Download or read book Strong and Weak Topology Probed by Surface Science written by Christian Pauly and published by Springer. This book was released on 2016-01-22 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Christian Pauly demonstrates the strong topological properties of the technologically relevant phase change materials Sb2Te3 and Ge2Sb2Te5 by using two powerful techniques for mapping the surface electronic structure: scanning tunneling spectroscopy (STS) and angle-resolved photoemission spectroscopy (ARPES). In the case of a phase change material, this opens up the possibility of switching between an insulating amorphous and a conducting topological phase on nanosecond-time scales. Moreover, the author presents first experimental results of a weak topological insulator, namely on the bismuth-based graphene-like sheet system Bi14Rh3I9, revealing a topologically protected one-dimensional edge channel as its fingerprint. The edge state is as narrow as 0.8 nm, making it extremely attractive to device physics. Those strong and weak topological insulators are a new phase of quantum matter giving rise to robust boundary states which are protected from backscattering and localization.
Download or read book Topological Insulators written by Shun-Qing Shen and published by Springer Science & Business Media. This book was released on 2013-01-11 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Topological insulators are insulating in the bulk, but process metallic states present around its boundary owing to the topological origin of the band structure. The metallic edge or surface states are immune to weak disorder or impurities, and robust against the deformation of the system geometry. This book, the first of its kind on topological insulators, presents a unified description of topological insulators from one to three dimensions based on the modified Dirac equation. A series of solutions of the bound states near the boundary are derived, and the existing conditions of these solutions are described. Topological invariants and their applications to a variety of systems from one-dimensional polyacetalene, to two-dimensional quantum spin Hall effect and p-wave superconductors, and three-dimensional topological insulators and superconductors or superfluids are introduced, helping readers to better understand this fascinating new field. This book is intended for researchers and graduate students working in the field of topological insulators and related areas. Shun-Qing Shen is a Professor at the Department of Physics, the University of Hong Kong, China.
Download or read book Theoretical Study on Correlation Effects in Topological Matter written by Hiroki Isobe and published by Springer. This book was released on 2017-04-04 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis elucidates electron correlation effects in topological matter whose electronic states hold nontrivial topological properties robust against small perturbations. In addition to a comprehensive introduction to topological matter, this thesis provides a new perspective on correlated topological matter. The book comprises three subjects, in which electron correlations in different forms are considered. The first focuses on Coulomb interactions for massless Dirac fermions. Using a perturbative approach, the author reveals emergent Lorentz invariance in a low-energy limit and discusses how to probe the Lorentz invariance experimentally. The second subject aims to show a principle for synthesizing topological insulators with common, light elements. The interplay between the spin–orbit interaction and electron correlation is considered, and Hund's rule and electron filling are consequently found to play a key role for a strong spin–orbit interaction important for topological insulators. The last subject is classification of topological crystalline insulators in the presence of electron correlation. Unlike non-interacting topological insulators, such two- and three-dimensional correlated insulators with mirror symmetry are demonstrated to be characterized, respectively, by the Z4 and Z8 group by using the bosonization technique and a geometrical consideration.
Download or read book Physics of Graphene written by Hideo Aoki and published by Springer Science & Business Media. This book was released on 2013-12-17 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a state of the art report of the knowledge accumulated in graphene research. The fascination with graphene has been growing very rapidly in recent years and the physics of graphene is now becoming one of the most interesting as well as the most fast-moving topics in condensed-matter physics. The Nobel prize in physics awarded in 2010 has given a tremendous impetus to this topic. The horizon of the physics of graphene is ever becoming wider, where physical concepts go hand in hand with advances in experimental techniques. Thus this book is expanding the interests to not only transport but optical and other properties for systems that include multilayer as well as monolayer graphene systems. The book comprises experimental and theoretical knowledge. The book is also accessible to graduate students.
Download or read book Magneto spectroscopy of Dirac Matter written by Thanyanan Phuphachong and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis reports on the study under magnetic field of the electronic properties of relativistic-like Dirac fermions in two Dirac systems: graphene and topological insulators. Their analogies with high-energy physics and their potential applications have attracted great attention for fundamental research in condensed matter physics. The carriers in these two materials obey a Dirac Hamiltonian and the energy dispersion is analogous to that of the relativistic particles. The particle rest mass is related to the band gap of the Dirac material, with the Fermi velocity replacing the speed of light. Graphene has been considered as a “role model”, among quantum solids, that allows us to study the relativistic behavior of massless Dirac fermions satisfying a linear dispersion. When a Dirac system possesses a nonzero gap, we have massive Dirac fermions. Massless and massive Dirac fermions were studied in high-mobility multilayer epitaxial graphene and in topological crystalline insulators Pb1-xSnxSe and Pb1-xSnxTe. The latter system is a new class of topological materials where the bulk states are insulating but the surface states are conducting. This particular aspect results from the inversion of the lowest conduction and highest valence bulk bands having different parities, leading to a topological phase transition. Infrared magneto-spectroscopy is an ideal technique to probe these zero-gap or narrow gap materials since it provides quantitative information about the bulk parameters via the Landau quantization of the electron states. In particular, the topological phase transition can be characterized by a direct measurement of the topological index.
Download or read book Rich Quasiparticle Properties In Layered Graphene related Systems written by Ming-fa Lin and published by World Scientific. This book was released on 2023-12-27 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive book delves into the fascinating world of quasiparticle properties of graphene-related materials. The authors thoroughly explore the intricate effects of intrinsic and extrinsic interactions on the material's properties, while unifying the single-particle and many-particle properties through the development of a theoretical framework. The book covers a wide range of research topics, including long-range Coulomb interactions, dynamic charge density waves, Friedel oscillations and plasmon excitations, as well as optical reflection and transmission spectra of thin films. Also it highlights the crucial roles of inelastic Coulomb scattering and optical scattering in the quasiparticle properties of layered systems, and the impact of crystal symmetry, number of layers, and stacking configuration on their uniqueness. Furthermore, the authors explore the topological properties of quasiparticles, including 2D time-reversal-symmetry protected topological insulators with quantum spin Hall effect, and rhombohedral graphite with Dirac nodal lines. Meanwhile, the book examines the gate potential application for creating topological localized states and shows topological invariants of 2D Dirac fermions, and binary Z2 topological invariants under chiral symmetry. The calculated results are consistent with the present experimental observations, establishing it as a valuable resource for individuals interested in the quasiparticle properties of novel materials.
Download or read book Electronic Transport in Dirac Materials graphene and a Topological Insulator Bi2Se3 written by Sungjae Cho and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Topological Insulators written by Inamuddin and published by Materials Research Forum LLC. This book was released on 2024-01-15 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: A topological insulator is an area that has yet to be fully explored and developed. The charge-induced bandgap fluctuation in the best-known bismuth-chalcogenide-based topological insulators is approximately 10MeV in magnitude. The major focus has shifted to the investigation of the presence of high-symmetry electronic bands as well as the utilization of easily produced materials. As the subject of topological insulators is still in the nascent stage, there is growing research and knowledge in the emerging field. This book is intended to provide the readers with an understanding of the needs and application of these materials. Keywords: Topological Insulators, Insulators, One-Dimensional Topological Insulators, Graphene, Magnetic Topological Insulator, Antiferromagnetic Phase, Ferromagnetic Phase, Topological Superconductor, Nonlinear Optical Behavior, Saturable Absorber, Quantum, Band Gap, Photonic Topological Insulators.
Download or read book Transport of dirac fermions on the surface of strong topological insulator and graphene written by Arijit Kundu and published by . This book was released on 2012 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Elemental Graphene Analogues written by D.J. Fisher and published by Materials Research Forum LLC. This book was released on 2017-06-01 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the greatest revolutions in materials science in recent years has been the literal renaissance of age-old materials in new and unexpected guises and possessing correspondingly astounding properties. There was once a time, for instance, when textbooks declared that only metals could offer any progress in superconduction. Since then, familiar perovskites – and even humble magnesium boride – have been recognised as being so-called ‘room-temperature’ superconductors. Carbon in particular has benefited from this revolution and has now found application as routinely deposited diamond coatings and as C60 ‘buckyballs’. The most recent innovation has been the discovery and preparation of graphene; single-monolayer carbon having a remarkable strength. This success has naturally led researchers to ask whether other materials might also be prepared in an analogous monolayer form and offer similarly amazing properties. The present monograph summarizes all of the work carried out on such monolayer materials up to the beginning of 2017, with attention being restricted to those, like graphene, being composed of a single element. Most of the work done so far on these ‘elemental graphene analogues’ has been theoretical, but the existing experimental data suggest that they may well become as useful as graphene.
Download or read book Topological Semimetals written by David J. Fisher and published by Materials Research Forum LLC. This book was released on 2019-04-20 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Topological semimetals are quantum materials that are not only extremely interesting from a theoretical point of view but also have a great potential for technological applications in which superconducting, semiconducting and other semimetal behaviors are involved. Keywords: Quantum Materials, Macroscopic Quantum Phenomena, Topological Semimetals, Dirac Semimetals, Weyl Semimetals, Nodal-Line Semimetals, Antimony and Antimonides, Antimonene, Arsenides, Bismuthides, Boron, Borides, Borophene, Carbon and Carbides, Chalcogenides, Nitrides, Phosphorus, Phosphides, Silicides, Topological Metals, Topological States of Matter.
Download or read book Scattering from the Single Dirac Cone written by Lindsay Gorman and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dirac Cones in Germanene PT 111 written by Carmel Dansou and published by . This book was released on 2018 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Natural Mechanical Topological Insulators written by Joshua R. Chiel and published by . This book was released on 2020 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we explore mechanical analogs of electronic topological insulators. We develop continuum models for the mechanical instability and spontaneous symmetry breaking for monolayer antimonene and bilayer graphene. We find that walls form between domains corresponding to different symmetry breaking minima. These domain walls are solitons in our model. Perturbations about the symmetry breaking equilibria propagate as waves with a gapped dispersion in the bulk but there is a gapless mode with linear dispersion that propagates along the domain wall in a manner reminiscent of the electronic edge modes of a topological insulator. We establish that monolayer antimonene is a mechanical topological insulator by demonstrating a mapping between our continuum model and an underlying Dirac equation of the symmetry class BDI which is known to be a topological insulator in one dimension and a weak topological insulator in two dimensions. Following a similar argument we expect that bilayer graphene as well is a weak topological insulator in two dimensions. We surmise that the effects studied here (namely low scale symmetry breaking, strain solitons and gapless edge modes) are not limited to antimonene and bilayer graphene but are common features of two dimensional materials.
Download or read book Berry Phases in Electronic Structure Theory written by David Vanderbilt and published by Cambridge University Press. This book was released on 2018-11 with total page 395 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introduction to the role of Berry phases in our modern understanding of the physics of electrons in solids.
