Spin-current State in Anisotropic Triangular Heisenberg Model

AbstractFor next-generation technology, magnetic systems are of interest due to the natural ability to store information and, through spin transport, propagate this information for logic functions. Controlling the magnetization state through currents has proven energy inefficient. Multiferroic thin-film heterostructures, combining ferroelectric and ferromagnetic orders, hold promise for energy efficient electronics. The electric field control of magnetic order is expected to reduce energy dissipation by 2–3 orders of magnitude relative to the current state-of-the-art. The coupling between electrical and magnetic orders in multiferroic and magnetoelectric thin-film heterostructures relies on interfacial coupling though magnetic exchange or mechanical strain and the correlation between domains in adjacent functional ferroic layers. We review the recent developments in electrical control of magnetism through artificial magnetoelectric heterostructures, domain imprint, emergent physics and device paradigms for magnetoelectric logic, neuromorphic devices, and hybrid magnetoelectric/spin-current-based applications. Finally, we conclude with a discussion of experiments that probe the crucial dynamics of the magnetoelectric switching and optical tuning of ferroelectric states towards all-optical control of magnetoelectric switching events.

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Chiral magnetism: a geometric perspective

SciPost Physics ◽

10.21468/scipostphys.10.3.078 ◽

2021 ◽

Vol 10 (3) ◽

Author(s):

Daniel Hill ◽

Valeriy Slastikov ◽

Oleg Tchernyshyov

Keyword(s):

Magnetic Field ◽

Excited States ◽

Ground State ◽

Heisenberg Model ◽

Parallel Transport ◽

Spin Current ◽

Theory Of Relativity ◽

Spacetime Curvature ◽

Spatial Dimensions ◽

Moriya Interaction

We discuss a geometric perspective on chiral ferromagnetism. Much like gravity becomes the effect of spacetime curvature in theory of relativity, the Dzyaloshinski-Moriya interaction arises in a Heisenberg model with nontrivial spin parallel transport. The Dzyaloshinskii-Moriya vectors serve as a background SO(3) gauge field. In 2 spatial dimensions, the model is partly solvable when an applied magnetic field matches the gauge curvature. At this special point, solutions to the Bogomolny equation are exact excited states of the model. We construct a variational ground state in the form of a skyrmion crystal and confirm its viability by Monte Carlo simulations. The geometric perspective offers insights into important problems in magnetism, e.g., conservation of spin current in the presence of chiral interactions.

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ESEM - A multipurpose surface Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144607 ◽

1986 ◽

Vol 44 ◽

pp. 632-633 ◽

Cited By ~ 2

Author(s):

G.D. Danilatos

Keyword(s):

Electron Microscope ◽

Room Temperature ◽

Environmental Scanning ◽

Gas Composition ◽

Saturated Water Vapor ◽

Surface Electron ◽

Current State ◽

Saturated Water ◽

New Type ◽

Temperature And Pressure

Over recent years a new type of electron microscope - the environmental scanning electron microscope (ESEM) - has been developed for the examination of specimen surfaces in the presence of gases. A detailed series of reports on the system has appeared elsewhere. A review summary of the current state and potential of the system is presented here.The gas composition, temperature and pressure can be varied in the specimen chamber of the ESEM. With air, the pressure can be up to one atmosphere (about 1000 mbar). Environments with fully saturated water vapor only at room temperature (20-30 mbar) can be easily maintained whilst liquid water or other solutions, together with uncoated specimens, can be imaged routinely during various applications.

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Recent applications of TEM to the study of interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174679 ◽

1990 ◽

Vol 48 (4) ◽

pp. 308-309

Author(s):

C. Barry Carter

Keyword(s):

High Resolution ◽

Sample Preparation ◽

Grain Boundaries ◽

Diffuse Scattering ◽

Imaging Techniques ◽

Amorphous Material ◽

Contrast Imaging ◽

Current State ◽

Actual Nature ◽

High Resolution Images

This paper will review the current state of understanding of interface structure and highlight some of the future needs and problems which must be overcome. The study of this subject can be separated into three different topics: 1) the fundamental electron microscopy aspects, 2) material-specific features of the study and 3) the characteristics of the particular interfaces. The two topics which are relevant to most studies are the choice of imaging techniques and sample preparation. The techniques used to study interfaces in the TEM include high-resolution imaging, conventional diffraction-contrast imaging, and phase-contrast imaging (Fresnel fringe images, diffuse scattering). The material studied affects not only the characteristics of the interfaces (through changes in bonding, etc.) but also the method used for sample preparation which may in turn have a significant affect on the resulting image. Finally, the actual nature and geometry of the interface must be considered. For example, it has become increasingly clear that the plane of the interface is particularly important whenever at least one of the adjoining grains is crystalline.A particularly productive approach to the study of interfaces is to combine different imaging techniques as illustrated in the study of grain boundaries in alumina. In this case, the conventional imaging approach showed that most grain boundaries in ion-thinned samples are grooved at the grain boundary although the extent of this grooving clearly depends on the crystallography of the surface. The use of diffuse scattering (from amorphous regions) gives invaluable information here since it can be used to confirm directly that surface grooving does occur and that the grooves can fill with amorphous material during sample preparation (see Fig. 1). Extensive use of image simulation has shown that, although information concerning the interface can be obtained from Fresnel-fringe images, the introduction of artifacts through sample preparation cannot be lightly ignored. The Fresnel-fringe simulation has been carried out using a commercial multislice program (TEMPAS) which was intended for simulation of high-resolution images.

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Proteasome inhibitors as therapeutics

Essays in Biochemistry ◽

10.1042/bse0410205 ◽

2005 ◽

Vol 41 ◽

pp. 205-218

Author(s):

Constantine S. Mitsiades ◽

Nicholas Mitsiades ◽

Teru Hideshima ◽

Paul G. Richardson ◽

Kenneth C. Anderson

Keyword(s):

Multiple Myeloma ◽

Drug Class ◽

Proteasome Inhibitors ◽

Cell Cycle Regulators ◽

Current State ◽

Intracellular Mechanism ◽

Ubiquitin Proteasome ◽

Proteasome Pathway ◽

Hodgkin's Lymphomas ◽

Clinical Research Data

The ubiquitin–proteasome pathway is a principle intracellular mechanism for controlled protein degradation and has recently emerged as an attractive target for anticancer therapies, because of the pleiotropic cell-cycle regulators and modulators of apoptosis that are controlled by proteasome function. In this chapter, we review the current state of the field of proteasome inhibitors and their prototypic member, bortezomib, which was recently approved by the U.S. Food and Drug Administration for the treatment of advanced multiple myeloma. Particular emphasis is placed on the pre-clinical research data that became the basis for eventual clinical applications of proteasome inhibitors, an overview of the clinical development of this exciting drug class in multiple myeloma, and a appraisal of possible uses in other haematological malignancies, such non-Hodgkin's lymphomas.

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Behavioral Genetics: Concepts for Research and Practice in Language Development and Disorders

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.3805.1126 ◽

1995 ◽

Vol 38 (5) ◽

pp. 1126-1142 ◽

Cited By ~ 14

Author(s):

Jeffrey W. Gilger

Keyword(s):

Language Development ◽

Behavioral Genetics ◽

State Of The Art ◽

Genetic Research ◽

Great Promise ◽

Behavioral Genetic ◽

Fine Grained ◽

Future Goals ◽

Current State ◽

Research Designs

This paper is an introduction to behavioral genetics for researchers and practioners in language development and disorders. The specific aims are to illustrate some essential concepts and to show how behavioral genetic research can be applied to the language sciences. Past genetic research on language-related traits has tended to focus on simple etiology (i.e., the heritability or familiality of language skills). The current state of the art, however, suggests that great promise lies in addressing more complex questions through behavioral genetic paradigms. In terms of future goals it is suggested that: (a) more behavioral genetic work of all types should be done—including replications and expansions of preliminary studies already in print; (b) work should focus on fine-grained, theory-based phenotypes with research designs that can address complex questions in language development; and (c) work in this area should utilize a variety of samples and methods (e.g., twin and family samples, heritability and segregation analyses, linkage and association tests, etc.).

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Endovascular management of ruptured abdominal aortic aneurysms and acute aortic dissections

VASA ◽

10.1024/0301-1526/a000760 ◽

2019 ◽

Vol 48 (1) ◽

pp. 35-46

Author(s):

Stephen Hofmeister ◽

Matthew B. Thomas ◽

Joseph Paulisin ◽

Nicolas J. Mouawad

Keyword(s):

Abdominal Aortic Aneurysms ◽

Rapid Identification ◽

Aortic Aneurysms ◽

Endovascular Interventions ◽

Current State ◽

Technological Advances ◽

Abdominal Aortic ◽

Ruptured Abdominal Aortic Aneurysms ◽

Vascular Emergencies ◽

Aortic Dissections

Abstract. The management of vascular emergencies is dependent on rapid identification and confirmation of the diagnosis with concurrent patient stabilization prior to immediate transfer to the operating suite. A variety of technological advances in diagnostic imaging as well as the advent of minimally invasive endovascular interventions have shifted the contemporary treatment algorithms of such pathologies. This review provides a comprehensive discussion on the current state and future trends in the management of ruptured abdominal aortic aneurysms as well as acute aortic dissections.

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Transcranial Electrical Stimulation in Post-Stroke Cognitive Rehabilitation

European Psychologist ◽

10.1027/1016-9040/a000238 ◽

2016 ◽

Vol 21 (1) ◽

pp. 55-64 ◽

Cited By ~ 4

Author(s):

Silvia Convento ◽

Cristina Russo ◽

Luca Zigiotto ◽

Nadia Bolognini

Keyword(s):

Electrical Stimulation ◽

Cognitive Rehabilitation ◽

Cognitive Disorders ◽

Spatial Neglect ◽

Transcranial Electrical Stimulation ◽

Clinical Settings ◽

Post Stroke ◽

Neuropsychological Disorders ◽

Current State ◽

Stimulation Technique

Abstract. Cognitive rehabilitation is an important area of neurological rehabilitation, which aims at the treatment of cognitive disorders due to acquired brain damage of different etiology, including stroke. Although the importance of cognitive rehabilitation for stroke survivors is well recognized, available cognitive treatments for neuropsychological disorders, such as spatial neglect, hemianopia, apraxia, and working memory, are overall still unsatisfactory. The growing body of evidence supporting the potential of the transcranial Electrical Stimulation (tES) as tool for interacting with neuroplasticity in the human brain, in turn for enhancing perceptual and cognitive functions, has obvious implications for the translation of this noninvasive brain stimulation technique into clinical settings, in particular for the development of tES as adjuvant tool for cognitive rehabilitation. The present review aims at presenting the current state of art concerning the use of tES for the improvement of post-stroke visual and cognitive deficits (except for aphasia and memory disorders), showing the therapeutic promises of this technique and offering some suggestions for the design of future clinical trials. Although this line of research is still in infancy, as compared to the progresses made in the last years in other neurorehabilitation domains, current findings appear very encouraging, supporting the development of tES for the treatment of post-stroke cognitive impairments.

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