Discovery of Co-existing Non-collinear Spin Textures in D2d Heusler Compounds


Book Description

Non-collinear spin textures have attracted significant attention due to their topological nature, emergent electromagnetic properties, and potential spintronic and magnonic device applications. This book explores the physical properties of distinct spin textures in D2d compounds. The main goals of the work are (a) discovering new spin textures in D2d Heusler compounds and studying their detailed properties to enrich the field of non-collinear magnetism (b) optimizing the nano-track geometry and generating isolated and single chains of nano-objects that will establish new hallmarks for technological applications (c) studying the stability of spin textures with magnetic fields and temperatures and finding a way to observe the striking behavior of spin textures near the specimen edges. The first few chapters provide a brief overview of spin textures such as Bloch and Néel skyrmions. In the experimental methods section, the author shows how to identify the single-crystalline grains of a polycrystalline sample, how to make single-crystalline thin specimens and nano-tracks, and then provides explicit descriptions of different imaging techniques performed on a transmission electron microscope. This part will be valuable for beginners wishing to conduct research in experimental nano-magnetism and transmission electron microscope imaging. The core results of the book are presented in four chapters, describing the discovery of several new and unanticipated spin textures, namely square-shaped antiskyrmions, elliptical Bloch skyrmions, fractional antiskyrmions, fractional Bloch skyrmions and elongated (anti)skyrmions in a single D2d Heusler compound. It is shown that these textures can be understood by a combination of dipole-dipole interactions and a chiral vector exchange that makes it possible to stabilize various spin textures even in the same compound. The D2d compounds are the first non-centrosymmetric systems shown to host several co-existing non-collinear spin textures.




Magneto-transport Properties of Skyrmions and Chiral Spin Structures in MnSi


Book Description

This book provides extensive and novel insights into transport phenomena in MnSi, paving the way for applying the topology and chirality of spin textures to the development of spintronics devices. In particular, it describes in detail the key measurements, e.g. magnetoresistance and nonlinear electronic transport, and multiple material-fabrication techniques based on molecular beam epitaxy, ion-beam microfabrication and micromagnetic simulation. The book also reviews key aspects of B20-type MnSi chiral magnets, which host magnetic skyrmions, nanoscale objects formed by helical spatial spin structures. Readers are then introduced to cutting-edge findings on the material. Furthermore, by reviewing the author’s successful experiments, the book provides readers with a valuable update on the latest achievements in the measurement and fabrication of magnetic materials in spintronics.




Spin Current


Book Description

In a new branch of physics and technology, called spin-electronics or spintronics, the flow of electrical charge (usual current) as well as the flow of electron spin, the so-called "spin current", are manipulated and controlled together. This book is intended to provide an introduction and guide to the new physics and applications of spin current.




Magnetic Multilayers


Book Description

This book focuses on an increasingly important area of materials science and technology, namely, the fabrication and properties of artificial materials where slabs of magnetized materials are sandwiched between slabs of nonmagnetized materials. It includes reviews by experts on the theory and descriptions of the various experimental techniques such as those using nuclear or electron spin probes, as well as optical, X-ray or neutron probes. It also reviews potential applications such as the giant magnetoresistance, and one specialized preparation technique, the electrodeposition. The various chapters are tutorial in nature, making the subject accessible to nonspecialists, as well as useful to researchers in the field.




2D Monoelemental Materials (Xenes) and Related Technologies


Book Description

Monoelemental 2D materials called Xenes have a graphene-like structure, intra-layer covalent bond, and weak van der Waals forces between layers. Materials composed of different groups of elements have different structures and rich properties, making Xenes materials a potential candidate for the next generation of 2D materials. 2D Monoelemental Materials (Xenes) and Related Technologies: Beyond Graphene describes the structure, properties, and applications of Xenes by classification and section. The first section covers the structure and classification of single-element 2D materials, according to the different main groups of monoelemental materials of different components and includes the properties and applications with detailed description. The second section discusses the structure, properties, and applications of advanced 2D Xenes materials, which are composed of heterogeneous structures, produced by defects, and regulated by the field. Features include: Systematically detailed single element materials according to the main groups of the constituent elements Classification of the most effective and widely studied 2D Xenes materials Expounding upon changes in properties and improvements in applications by different regulation mechanisms Discussion of the significance of 2D single-element materials where structural characteristics are closely combined with different preparation methods and the relevant theoretical properties complement each other with practical applications Aimed at researchers and advanced students in materials science and engineering, this book offers a broad view of current knowledge in the emerging and promising field of 2D monoelemental materials.




Chiral Solitons


Book Description

This review volume on topological and nontopological chiral solitons presents a global view on the current developments of this field in particle and nuclear physics. The book addresses problems in quantization, restoration of translational and rotational symmetry, and the field theoretical approach to solitons which are common problems in the field of solitons. Primarily aimed for graduate students and the novice in the field, the collected articless cover a broad spectrum of topics in formalism as well as phenomenology.




The Role of Topology in Materials


Book Description

This book presents the most important advances in the class of topological materials and discusses the topological characterization, modeling and metrology of materials. Further, it addresses currently emerging characterization techniques such as optical and acoustic, vibrational spectroscopy (Brillouin, infrared, Raman), electronic, magnetic, fluorescence correlation imaging, laser lithography, small angle X-ray and neutron scattering and other techniques, including site-selective nanoprobes. The book analyzes the topological aspects to identify and quantify these effects in terms of topology metrics. The topological materials are ubiquitous and range from (i) de novo nanoscale allotropes of carbons in various forms such as nanotubes, nanorings, nanohorns, nanowalls, peapods, graphene, etc. to (ii) metallo-organic frameworks, (iii) helical gold nanotubes, (iv) Möbius conjugated polymers, (v) block co-polymers, (vi) supramolecular assemblies, to (vii) a variety of biological and soft-matter systems, e.g. foams and cellular materials, vesicles of different shapes and genera, biomimetic membranes, and filaments, (viii) topological insulators and topological superconductors, (ix) a variety of Dirac materials including Dirac and Weyl semimetals, as well as (x) knots and network structures. Topological databases and algorithms to model such materials have been also established in this book. In order to understand and properly characterize these important emergent materials, it is necessary to go far beyond the traditional paradigm of microscopic structure-property-function relationships to a paradigm that explicitly incorporates topological aspects from the outset to characterize and/or predict the physical properties and currently untapped functionalities of these advanced materials. Simulation and modeling tools including quantum chemistry, molecular dynamics, 3D visualization and tomography are also indispensable. These concepts have found applications in condensed matter physics, materials science and engineering, physical chemistry and biophysics, and the various topics covered in the book have potential applications in connection with novel synthesis techniques, sensing and catalysis. As such, the book offers a unique resource for graduate students and researchers alike.




Introduction to Frustrated Magnetism


Book Description

The field of highly frustrated magnetism has developed considerably and expanded over the last 15 years. Issuing from canonical geometric frustration of interactions, it now extends over other aspects with many degrees of freedom such as magneto-elastic couplings, orbital degrees of freedom, dilution effects, and electron doping. Its is thus shown here that the concept of frustration impacts on many other fields in physics than magnetism. This book represents a state-of-the-art review aimed at a broad audience with tutorial chapters and more topical ones, encompassing solid-state chemistry, experimental and theoretical physics.




The Vortex State


Book Description

One of the most spectacular consequences of the description of the superfluid condensate in superfluid He or in superconductors as a single macroscopic quantum state is the quantization of circulation, resulting in quantized vortex lines. This book draws no distinction between superfluid He3 and He4 and superconductors. The reader will find the essential introductory chapters and the most recent theoretical and experimental progress in our understanding of the vortex state in both superconductors and superfluids, from lectures given by leading experts in the field, both experimentalists and theoreticians, who gathered in Cargèse for a NATO ASI. The peculiar features related to short coherence lengths, 2D geometry, high temperatures, disorder, and pinning are thoroughly discussed.