Download or read book Magneto optical Study of Spin Polarized States in Strongly Correlated Systems written by Marta Bastjan and published by . This book was released on 2008 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Strongly Correlated Fermions and Bosons in Low Dimensional Disordered Systems written by Igor V. Lerner and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physics of strongly correlated fermions and bosons in a disordered envi ronment and confined geometries is at the focus of intense experimental and theoretical research efforts. Advances in material technology and in low temper ature techniques during the last few years led to the discoveries of new physical of atomic gases and a possible metal phenomena including Bose condensation insulator transition in two-dimensional high mobility electron structures. Situ ations were the electronic system is so dominated by interactions that the old concepts of a Fermi liquid do not necessarily make a good starting point are now routinely achieved. This is particularly true in the theory of low dimensional systems such as carbon nanotubes, or in two dimensional electron gases in high mobility devices where the electrons can form a variety of new structures. In many of these sys tems disorder is an unavoidable complication and lead to a host of rich physical phenomena. This has pushed the forefront of fundamental research in condensed matter towards the edge where the interplay between many-body correlations and quantum interference enhanced by disorder has become the key to the understand ing of novel phenomena.
Download or read book Spin Electronics written by David D. Awschalom and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: The history of scientific research and technological development is replete with examples of breakthroughs that have advanced the frontiers of knowledge, but seldom does it record events that constitute paradigm shifts in broad areas of intellectual pursuit. One notable exception, however, is that of spin electronics (also called spintronics, magnetoelectronics or magnetronics), wherein information is carried by electron spin in addition to, or in place of, electron charge. It is now well established in scientific and engineering communities that Moore's Law, having been an excellent predictor of integrated circuit density and computer performance since the 1970s, now faces great challenges as the scale of electronic devices has been reduced to the level where quantum effects become significant factors in device operation. Electron spin is one such effect that offers the opportunity to continue the gains predicted by Moore's Law, by taking advantage of the confluence of magnetics and semiconductor electronics in the newly emerging discipline of spin electronics. From a fundamental viewpoine, spin-polarization transport in a material occurs when there is an imbalance of spin populations at the Fermi energy. In ferromagnetic metals this imbalance results from a shift in the energy states available to spin-up and spin-down electrons. In practical applications, a ferromagnetic metal may be used as a source of spin-polarized electronics to be injected into a semiconductor, a superconductor or a normal metal, or to tunnel through an insulating barrier.
Download or read book Magneto optical Studies of InGaAs Quantum Wells and Devices Used for Spintronics Applications written by Tariq Ali and published by . This book was released on 2011 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: AbstractSpintronics has been one of the most rapidly developing research areas in condensed matter physics. Exploiting the electron's spin degree of freedom is hoped to yield new and novel technological applications. The ability to generate a non-equilibrium spin population, to manipulate the spins, and to be able to detect them have been the most intensely studied subjects in this research area. In this dissertation, spin injection from an Fe (Iron) ferromagnetic spin polarizing contact into two dimensional semiconductor hetero-structures were investigated using a device called a "Spin-LED" also known as a Spin Light Emitting Diode. Due to its high Curie temperature, Fe is a very promising candidate for practical applications at room temperature. This dissertation is comprised of two separate experimental studies outlined as follows.1. We have investigated the Polarization of the Spin LEDs as function of Bias. In addition to the exciton we see a feature called "LV" (Low Voltage) that is bias and temperature dependent. We have compared the Spin life time TS measured for the exciton, LV feature in the device (Spin LED) and for the exciton in the unprocessed InGaAs QW. The LV feature shows polarization in excess of 70% and the polarization changes sign as we increase the magnetic field from B = 0 Tesla to B = 7 Tesla.2. We see intensity oscillations in for the photoluminescence for exciton in the InGaAs QWs. We attribute these oscillations to the Optical Aharonov-Bohm effect. A shift in the oscillations has been observed when the sample relative angle with respect to the magnetic field is changed. These oscillations are present only in the Faraday's geometry and disappear in the Voigt geometry.
Download or read book Spin Current written by Sadamichi Maekawa and published by Oxford University Press. This book was released on 2017 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Spectroscopic Study on Charge Spin Orbital Coupled Phenomena in Mott Transition Oxides written by Masaki Uchida and published by Springer Science & Business Media. This book was released on 2013-02-02 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis the author presents the results of extensive spectroscopy experiments beyond the bounds of each transition element to clarify the origins of characteristic spectral features and charge dynamics in charge-spin-orbital coupled phenomena in Mott-transition oxides. Several counterpart 3d transition-metal oxides were adopted as model systems suitable for examining the mechanisms involved, and their electronic structures were systematically investigated using three main spectroscopy methods. Comparative studies on the charge dynamics and Mott transition features of transition-metal oxides were performed: Charge dynamics and thermoelectricity in a typical Mott transition system La1−xSrxVO3, charge dynamics in a doped valence-bond solid system (Ti1−xVx)2O3 and in layered nickelates R2-xSrxNiO4 with charge-ordering instability are investigated thoroughly. The results obtained successfully provide a number of novel insights into the emergent phenomena near the Mott transition.
Download or read book Magneto optics of Strongly Correlated Electron Systems in the Quantum Hall Effect written by Rizwan Ahmed Chughtai and published by . This book was released on 2006 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Spintronics written by Yongbing Xu and published by Springer. This book was released on 2015-10-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over two volumes and 1500 pages, the Handbook of Spintronics will cover all aspects of spintronics science and technology, including fundamental physics, materials properties and processing, established and emerging device technology and applications. Comprising 60 chapters from a large international team of leading researchers across academia and industry, the Handbook provides readers with an up-to-date and comprehensive review of this dynamic field of research. The opening chapters focus on the fundamental physical principles of spintronics in metals and semiconductors, including an introduction to spin quantum computing. Materials systems are then considered, with sections on metallic thin films and multilayers, magnetic tunnelling structures, hybrids, magnetic semiconductors and molecular spintronic materials. A separate section reviews the various characterisation methods appropriate to spintronics materials, including STM, spin-polarised photoemission, x-ray diffraction techniques and spin-polarised SEM. The third part of the Handbook contains chapters on the state of the art in device technology and applications, including spin valves, GMR and MTJ devices, MRAM technology, spin transistors and spin logic devices, spin torque devices, spin pumping and spin dynamics and other topics such as spin caloritronics. Each chapter considers the challenges faced by researchers in that area and contains some indications of the direction that future work in the field is likely to take. This reference work will be an essential and long-standing resource for the spintronics community.
Download or read book Low Dimensional Systems written by Tobias Brandes and published by Springer Science & Business Media. This book was released on 2000-04-05 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental progress over the past few years has made it possible to test a n- ber of fundamental physical concepts related to the motion of electrons in low dimensions. The production and experimental control of novel structures with typical sizes in the sub-micrometer regime has now become possible. In parti- lar, semiconductors are widely used in order to con?ne the motion of electrons in two-dimensional heterostructures. The quantum Hall e?ect was one of the ?rst highlights of the new physics that is revealed by this con?nement. In a further step of the technological development in semiconductor-heterostructures, other arti?cial devices such as quasi one-dimensional ‘quantum wires’ and ‘quantum dots’ (arti?cial atoms) have also been produced. These structures again di?er very markedly from three- and two-dimensional systems, especially in relation to the transport of electrons and the interaction with light. Although the technol- ical advances and the experimental skills connected with these new structures are progressing extremely fast, our theoretical understanding of the physical e?ects (such as the quantum Hall e?ect) is still at a very rudimentary level. In low-dimensional structures, the interaction of electrons with one another and with other degrees of freedoms such as lattice vibrations or light gives rise to new phenomena that are very di?erent from those familiar in the bulk ma- rial. The theoretical formulation of the electronic transport properties of small devices may be considered well-established, provided interaction processes are neglected.
Download or read book Magnetization Dynamics in Diluted Magnetic Semiconductor Heterostructures written by Martin Kneip and published by GRIN Verlag. This book was released on 2009-02-17 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doctoral Thesis / Dissertation from the year 2008 in the subject Physics - Theoretical Physics, grade: sehr gut (1,0), University of Dortmund, language: English, abstract: In this thesis spin dynamics in (Zn,Mn)Se/(Zn,Be)Se and (Cd,Mn)Te/(Cd,Mg)Te DMS quantum well heterostructures with a type-I band alignment are studied, where the carriers are quantum confined. Especially the important role of free carriers in heating of the Mn-system, by its interaction with photoexcited carriers with excess kinetic energy, and in the cooling of the Mn-system in the presence of cold background carriers, provided by modulation doping, is established. The studies are separated in three chapters. In the fourth chapter of this thesis, new results on energy and spin transfer between free carriers and Mn-ion system are presented. Contributions of direct heating of the Mn-system by photocarriers and indirect heating via nonequilibrium phonons are distinguished and their competition is discussed. In the fifth chapter dynamics of spin-lattice relaxation of magnetic Mn-ions in DMS QW heterostructures is investigated and new experimental studies on (Zn,Mn)Se/(Zn,Be)Se heterostructures are shown. Crucial for spintronic devices is the ability to tune the spin relaxation time precisely, as the spin relaxation time is important in double respects. On the one hand spin polarization must be conserved over long times and distances, if the spin shall be processed or stored in a region, which is spatial separated from the spin-injector. Especially for the possibility of utilizing spins as quantum bits for quantum information processing, long spin polarization is needed. On the other hand short spin relaxation time is needed for fast switching between different spin-states. For instance semiconductor lasers can be switched off extremely fast by reorientation of spin. This very relevant topic is devoted the sixth chapter, before the thesis is summarized in the last chapter. Especially for one of the biggest drawbacks for precise tuning, that the magnetization dynamics in DMS cannot be controlled separately from the static magnetization, solutions via electric field control of the magnetization dynamics or via the technological concept of “digital alloying” are presented.precise tuning, that the magnetization dynamics in DMS cannot be controlled separately from the static magnetization, solutions via electric field control of the magnetization dynamics or via the technological concept of “digital alloying” are presented.
Download or read book Magnetooptical Spectroscopy of the Rare Earth Compounds Development and Application written by Uygun V. Valiev and published by Scientific Research Publishing, Inc. USA. This book was released on 2012-01-05 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comparison of theory with experiment is made for rare-earth compounds with garnet structure and orthoaluminate whose optical, magnetic and magnetooptical features have been studied sufficiently well by now.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Treatise on Geophysics written by and published by Elsevier. This book was released on 2015-04-17 with total page 5604 pages. Available in PDF, EPUB and Kindle. Book excerpt: Treatise on Geophysics, Second Edition, is a comprehensive and in-depth study of the physics of the Earth beyond what any geophysics text has provided previously. Thoroughly revised and updated, it provides fundamental and state-of-the-art discussion of all aspects of geophysics. A highlight of the second edition is a new volume on Near Surface Geophysics that discusses the role of geophysics in the exploitation and conservation of natural resources and the assessment of degradation of natural systems by pollution. Additional features include new material in the Planets and Moon, Mantle Dynamics, Core Dynamics, Crustal and Lithosphere Dynamics, Evolution of the Earth, and Geodesy volumes. New material is also presented on the uses of Earth gravity measurements. This title is essential for professionals, researchers, professors, and advanced undergraduate and graduate students in the fields of Geophysics and Earth system science. Comprehensive and detailed coverage of all aspects of geophysics Fundamental and state-of-the-art discussions of all research topics Integration of topics into a coherent whole
Download or read book Grants and Awards written by National Science Foundation (U.S.) and published by . This book was released on with total page 746 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Of Semiconductors The Proceedings Of The 22nd International Conference In 3 Volumes written by David J Lockwood and published by World Scientific. This book was released on 1995-01-20 with total page 2858 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings review the progress in most aspects of semiconductor physics, including those related to materials, processing and devices. The conference continues the tradition of the ICPS series and these volumes include state-of-the-art lectures. The plenary and invited papers address areas of major interest.These volumes will serve as excellent material for researchers in semiconductor physics and related fields.
Download or read book Generation Detection and Manipulation of Skyrmions in Magnetic Nanostructures written by Huaiyang Yuan and published by Frontiers Media SA. This book was released on 2022-09-23 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Magnetism and Transport Phenomena in Spin Charge Coupled Systems on Frustrated Lattices written by Hiroaki Ishizuka and published by Springer. This book was released on 2015-07-13 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, magnetism and transport phenomena in spin-charge coupled systems on frustrated lattices are theoretically investigated, focusing on Ising-spin Kondo lattice models and using a combination of Monte Carlo simulation and other techniques such as variational calculations and perturbation theory. The emphasis of the study is on how the cooperation of spin-charge coupling and geometrical frustration affects the thermodynamic properties of the Kondo lattice models; it presents the emergence of various novel magnetic states, such as the partial disorder, loop-liquid, and spin-cluster states. The thesis also reveals that the magnetic and electronic states and transport properties of these models demonstrate peculiar features, such as Dirac half-metals, anomalous Hall insulators, and spin Hall effects. Study of novel magnetic states and exotic transport phenomena in Kondo lattice systems is a field experiencing rapid progress. The interplay of charge and spin degrees of freedom potentially gives rise to various novel phases and transport phenomena which are related to strongly correlated electrons, frustrated magnetism, and topological states of matter. The results presented in this thesis include numerical calculations that are free from approximations. Accordingly, they provide reliable reference values, both for studying magnetism and transports of related models and for experimentally exploring novel states of matter in metallic magnets.
