Charge Spin Transport Correlation In Local Electrical Spin Injection In Silicon

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Charge-spin Transport Correlation in Local Electrical Spin Injection in Silicon

Author : Jonas Tyler Beardsley
Publisher :
ISBN 13 :
Total Pages : 165 pages
Book Rating : 4.:/5 (99 download)

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Book Synopsis Charge-spin Transport Correlation in Local Electrical Spin Injection in Silicon by : Jonas Tyler Beardsley

Download or read book Charge-spin Transport Correlation in Local Electrical Spin Injection in Silicon written by Jonas Tyler Beardsley and published by . This book was released on 2014 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spintronics (the word is intended to combine "spin" with "electronics") is the study of spin dependent phenomena in solids, with a concentration on metals, semiconductors, and semiconductor heterostructures. These studies characterize the magnetic, electrical and optical properties of said materials due to the polarization of their spin populations. These fundamental relationships can yield important insights into spin interactions such as spin exchange, spin-orbit, and hyperfine interactions in solids. In a more narrow sense, spintronics refers to the study of spin polarized transport in metals and semiconductors. There are two complimentary methods of this applied spintronics: to manipulate the electronics properties of a system, for example the resistance or charge accumulation, by magnetic field or spin polarization, and to control spin and magnetic properties by electric currents or gate voltages. The ultimate goal of this is to enhance the functionality of conventional, charge based electronics. For example, a spin field effect transistor, which could change its resistance from high to low by changing the orientation of a magnetic field. In theory, these devices can operate more efficiently than those which operate entirely based on charge. This means that using spintronic elements in logic devices may be able to reduce the power usage and heat generation by computation.

Electrical Detection of Spin Transport in Silicon Two-Dimensional Electron Gas Systems

Author : Li-Te Chang
Publisher :
ISBN 13 :
Total Pages : 132 pages
Book Rating : 4.:/5 (17 download)

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Book Synopsis Electrical Detection of Spin Transport in Silicon Two-Dimensional Electron Gas Systems by : Li-Te Chang

Download or read book Electrical Detection of Spin Transport in Silicon Two-Dimensional Electron Gas Systems written by Li-Te Chang and published by . This book was released on 2015 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electrical detection of spin transport in a semiconductor (SC) channel is one of the key requirements to realize spintronics devices. Among various SC materials, the high-mobility two-dimensional electron gas (2DEG) confined in a modulation doped quantum well structure (MODQW) is of particular interest for device applications. This is because the high mobility promises for a long spin diffusion length of coherent transport as well as large spin signal for easy sensing. Meanwhile, the effective spin manipulation is achievable either by enhanced Rashba spin-orbit interaction from an asymmetric E-field structure, or by direct control of discrete density of states (DOS) within the quantum well structure. Despite of these merits, very few studies of direct electrical spin injection into 2DEG have been reported so far, mainly because of the difficulty in making reliable ferromagnetic (FM) contacts to the buried 2DEG channel. In literature, only a few reports in Si/SiO2 and III-V matrices are available up to now; however, electrical detection of spin transport in the high-mobility 2DEG in a Si/SiGe MODQW has not been reported. To make continuous progress of Si-based spintronics and to take full advantage of current CMOS technology, there is an urgent need to develop Si-based spintronics devices. In this thesis we present two related projects: first is spin injection in Ge; second is spin injection in Si two-dimensional electron gas (2DEG) system. It is the knowledge built up from the Ge project helps us successfully demonstrate electrical spin injection in Si 2DEG in a Si/SiGe MODQW using FM Mn-germanosilicide (Mn(Si0.7Ge0.3)x) end contacts, which is a new approach to circumvent the difficulty of etching process adopted for the typical spin valve devices. The experiments show that the spin-polarized electrons could be laterally injected into one side of the 2DEG confined at the Si/SiGe interface, and subsequently detected from the other side by the magnetoresistance (MR) of a FM/2DEG/FM spin valve. Most important of all, symmetric resistance steps were clearly observed from a series of FM/2DEG/FM spin valve devices with different channel lengths (Lch = 1.5~3.5 m), by which the spin diffusion length and spin lifetime are calculated to be 4.5 um and 16 ns at 1.9 K, respectively.

Spintronics Handbook, Second Edition: Spin Transport and Magnetism

Author : Evgeny Y. Tsymbal
Publisher : CRC Press
ISBN 13 : 0429784376
Total Pages : 530 pages
Book Rating : 4.4/5 (297 download)

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Book Synopsis Spintronics Handbook, Second Edition: Spin Transport and Magnetism by : Evgeny Y. Tsymbal

Download or read book Spintronics Handbook, Second Edition: Spin Transport and Magnetism written by Evgeny Y. Tsymbal and published by CRC Press. This book was released on 2019-05-20 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition offers an update on the single most comprehensive survey of the two intertwined fields of spintronics and magnetism, covering the diverse array of materials and structures, including silicon, organic semiconductors, carbon nanotubes, graphene, and engineered nanostructures. It focuses on seminal pioneering work, together with the latest in cutting-edge advances, notably extended discussion of two-dimensional materials beyond graphene, topological insulators, skyrmions, and molecular spintronics. The main sections cover physical phenomena, spin-dependent tunneling, control of spin and magnetism in semiconductors, and spin-based applications.

Handbook of Spin Transport and Magnetism

Author : Evgeny Y. Tsymbal
Publisher : CRC Press
ISBN 13 : 1439803773
Total Pages : 809 pages
Book Rating : 4.4/5 (398 download)

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Book Synopsis Handbook of Spin Transport and Magnetism by : Evgeny Y. Tsymbal

Download or read book Handbook of Spin Transport and Magnetism written by Evgeny Y. Tsymbal and published by CRC Press. This book was released on 2011-08-25 with total page 809 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past several decades, the research on spin transport and magnetism has led to remarkable scientific and technological breakthroughs, including Albert Fert and Peter Grünberg’s Nobel Prize-winning discovery of giant magnetoresistance (GMR) in magnetic metallic multilayers. Handbook of Spin Transport and Magnetism provides a comprehensive, balanced account of the state of the art in the field known as spin electronics or spintronics. It reveals how key phenomena first discovered in one class of materials, such as spin injection in metals, have been revisited decades later in other materials systems, including silicon, organic semiconductors, carbon nanotubes, graphene, and carefully engineered nanostructures. The first section of the book offers a historical and personal perspective of the field written by Nobel Prize laureate Albert Fert. The second section addresses physical phenomena, such as GMR, in hybrid structures of ferromagnetic and normal metals. The third section discusses recent developments in spin-dependent tunneling, including magnetic tunnel junctions with ferroelectric barriers. In the fourth section, the contributors look at how to control spin and magnetism in semiconductors. In the fifth section, they examine phenomena typically found in nanostructures made from metals, superconductors, molecular magnets, carbon nanotubes, quantum dots, and graphene. The final section covers novel spin-based applications, including advanced magnetic sensors, nonvolatile magnetoresistive random access memory, and semiconductor spin-lasers. The techniques and materials of spintronics have rapidly evolved in recent years, leading to vast improvements in hard drive storage and magnetic sensing. With extensive cross-references between chapters, this seminal handbook provides a complete guide to spin transport and magnetism across various classes of materials and structures.

Interactions Between Spin Transport and Dynamics Studied Using Spatially Resolved Imaging and Magnetic Resonance

Author : Michael Roy Page
Publisher :
ISBN 13 :
Total Pages : 234 pages
Book Rating : 4.:/5 (973 download)

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Book Synopsis Interactions Between Spin Transport and Dynamics Studied Using Spatially Resolved Imaging and Magnetic Resonance by : Michael Roy Page

Download or read book Interactions Between Spin Transport and Dynamics Studied Using Spatially Resolved Imaging and Magnetic Resonance written by Michael Roy Page and published by . This book was released on 2016 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, I explore the interactions that occur between transported spins and magnetization dynamics using spatially resolved imaging and magnetic resonance. The integration of spin transport and dynamics will be a crucial aspect of realizing spintronic devices, which seek to improve upon current charge based electronics. Rather than focusing on the charge degree of freedom as in traditional electronics, spintronics seeks to utilize the properties of the electron spin degree of freedom to revolutionize the fundamental operating principles of data processing and storage devices. Spintronics promises greater functionality and energy efficiency in devices based on electron spin. However, improved understanding and control of the spin degree of freedom is required for spintronics to reach its full potential. The work in this dissertation represents efforts towards addressing these requirements. I discuss my work relating to the development of a custom scanned probe microscope allowing simultaneous spatially resolved imaging while imposing transport in electrically active spintronic devices. Using this microscope, I correlate the switching of magnetic electrodes in a graphene spin valve to the resistance states by directly imaging the electrode magnetization configuration while simultaneously measuring the non-local magnetoresistance. I investigate interactions between a ferromagnet driven into resonance and proximal nitrogen vacancy centers in diamond. Spinwaves generated during the decay of the uniform mode driven to ferromagnetic resonance relax the diamond nitrogen vacancy center spins resulting in a change in the fluorescence intensity. This technique allows the study of transport of angular momentum between two separated spin systems, as well as the possibility for the nanoscale imaging of magnetization dynamics. I demonstrate Heusler alloy ferromagnetic materials as high spin polarization spin injectors for device applications by studying their magnetoresistive output as a function of composition at room and low temperatures. Spin injection efficiency is another important aspect in the performance of spintronic devices, and optimization of spin injection will be of importance in creating realistic devices. Another promising avenue for spin injection relies on the spin Hall effect. I discuss efforts at using the spin Hall effect in platinum to inject spins into an aluminum channel to be detected in another platinum electrode by the inverse spin Hall effect without the need for a ferromagnet, thus reducing complications resulting from the stray field of typical ferromagnetic injectors. I discuss exploration of spin pumping devices based on metallic and insulating ferromagnet/graphene bilayers using ferromagnetic resonance and electrical detection of the inverse spin Hall effect. Spin pumping represents another opportunity to study interactions of spin transport and magnetization dynamics, in this case leveraged for efficient spin injection. Finally, I perform magnetic resonance measurements of thin film iron germanium skyrmionic candidate materials. Skrymions are a candidate for high density and low power magnetic recording. Measuring the dynamics of these materials will be important for a full characterization of their properties. I demonstrate detection of multiple magnetic phases in this material, and show evidence of large internal fields, which may be of interest in stabilizing skrymions in thin films.

Introduction to Spintronics

Author : Supriyo Bandyopadhyay
Publisher : CRC Press
ISBN 13 : 148225557X
Total Pages : 650 pages
Book Rating : 4.4/5 (822 download)

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Book Synopsis Introduction to Spintronics by : Supriyo Bandyopadhyay

Download or read book Introduction to Spintronics written by Supriyo Bandyopadhyay and published by CRC Press. This book was released on 2015-09-18 with total page 650 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Spintronics provides an accessible, organized, and progressive presentation of the quantum mechanical concept of spin and the technology of using it to store, process, and communicate information. Fully updated and expanded to 18 chapters, this Second Edition:Reflects the explosion of study in spin-related physics, addressing seven

Spin Electronics

Author : David D. Awschalom
Publisher : Springer Science & Business Media
ISBN 13 : 9401705321
Total Pages : 216 pages
Book Rating : 4.4/5 (17 download)

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Book Synopsis Spin Electronics by : David D. Awschalom

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.

Spin Current

Author : Sadamichi Maekawa
Publisher : Oxford University Press
ISBN 13 : 0198787073
Total Pages : 541 pages
Book Rating : 4.1/5 (987 download)

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Book Synopsis Spin Current by : Sadamichi Maekawa

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.

Physics of Spin in Solids: Materials, Methods and Applications

Author : Samed Halilov
Publisher : Springer Science & Business Media
ISBN 13 : 1402027087
Total Pages : 260 pages
Book Rating : 4.4/5 (2 download)

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Book Synopsis Physics of Spin in Solids: Materials, Methods and Applications by : Samed Halilov

Download or read book Physics of Spin in Solids: Materials, Methods and Applications written by Samed Halilov and published by Springer Science & Business Media. This book was released on 2006-01-20 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most recent publications on spin-related phenomena focus on technological aspects of spin-dependent transport, with emphasis on the specific needs of spintronics. The present publication targets rather fundamental problems related to the physics of spin in solids, such as: (1) manifestation of spin and orbital polarization in spectroscopy, including valence and X-ray photoemission, magneto-optics, low-energy electron scattering on the surface; (2) application of new methods for interpretation and determination of magnetic low-lying excitations in the bulk and on the surface; (3) recent progress in evaluation of different type of magnetic forces including spin-orbit and exchange interaction, with subsequent determination of anisotropy and spin-ordering structure; (4) general problems of spin-dependent transport in semiconductors and metals, such as current-caused torque effect on spins at interfaces and spin injection in quantum dot systems; (5) problems in understanding the spin-dependent trends in unconventional superconductors; (6) many-body problems in solid state physics and recent progress in evaluation of self-energy effects; (7) fabrication of new magnetic materials with pre-programmed properties based on assembly from nano-particles, etc.

Handbook of Spin Transport and Magnetism

Author : Evgeny Y. Tsymbal
Publisher : CRC Press
ISBN 13 : 1439803781
Total Pages : 797 pages
Book Rating : 4.4/5 (398 download)

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Book Synopsis Handbook of Spin Transport and Magnetism by : Evgeny Y. Tsymbal

Download or read book Handbook of Spin Transport and Magnetism written by Evgeny Y. Tsymbal and published by CRC Press. This book was released on 2016-04-19 with total page 797 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past several decades, the research on spin transport and magnetism has led to remarkable scientific and technological breakthroughs, including Albert Fert and Peter Grunberg's Nobel Prize-winning discovery of giant magnetoresistance (GMR) in magnetic metallic multilayers. Handbook of Spin Transport and Magnetism provides a comprehensive, bal

Extrinsic Spin Relaxation in Silicon Spin Transport Devices

Author : Jing Li
Publisher :
ISBN 13 : 9781267249494
Total Pages : pages
Book Rating : 4.2/5 (494 download)

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Book Synopsis Extrinsic Spin Relaxation in Silicon Spin Transport Devices by : Jing Li

Download or read book Extrinsic Spin Relaxation in Silicon Spin Transport Devices written by Jing Li and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon is one promising semiconductor material to realize spin-based devices and circuits, not only because of its entrenchment in present-day charge-based microelectronics industry, but also due to its exceptionally long electron spin lifetime. This intrinsic spin lifetime of conduction electrons in bulk silicon was estimated by Yafet's theory assuming that intravalley electron-acoustic phonon scattering is the dominant spin-flip mechanism at equilibrium, which agrees with experimental results from early electron spin resonance measurements and recent spin transport measurements using ballistic hot-electron injection and detection. This dissertation details experimental observations of substantial electron spin relaxation in silicon due to extrinsic effects which do not originate from intravalley electron-acoustic phonon scattering. Spin transport in high electric field demonstrates a field-induced spin relaxation by phonon emission process during which electrons are scattered between conduction band valleys that reside on different crystal axes. Charge and spin transport measurements below 25 K demonstrate the existence of anomalous spin relaxation which stems from electron spin exchange interaction with bulk neutral donor spin. Using a two-dimensional finite-difference modeling scheme, spin relaxation during lateral spin transport near Si/SiO 2 electrostatic gate interface is confirmed to be a result of enhanced momentum scattering and exchange coupling related to interfacial defects. These findings of extrinsic spin relaxation mechanisms are important to the design of spin-based semiconductor devices where the condition of equilibrium and the symmetry of bulk silicon lattice are necessarily broken.

Spin Injection, Spin Transport and Spin-charge Conversion in Organic Semiconductors

Author : Sebastian Thomas Mooser
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (89 download)

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Book Synopsis Spin Injection, Spin Transport and Spin-charge Conversion in Organic Semiconductors by : Sebastian Thomas Mooser

Download or read book Spin Injection, Spin Transport and Spin-charge Conversion in Organic Semiconductors written by Sebastian Thomas Mooser and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Modeling and Simulation of Spin Transport and Precession in Silicon

Author : Jing Xu
Publisher : ProQuest
ISBN 13 : 9780549813941
Total Pages : pages
Book Rating : 4.8/5 (139 download)

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Book Synopsis Modeling and Simulation of Spin Transport and Precession in Silicon by : Jing Xu

Download or read book Modeling and Simulation of Spin Transport and Precession in Silicon written by Jing Xu and published by ProQuest. This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Spin-based semiconductor devices have received much research attention in recent years. Recently, spin injection, transport and detection have been realized in some research groups, paving a promising way to reduce device size and enhance efficiency in current semiconductor microelectronic technology. It is now necessary to set up mathematic models to simulate spin transport in pure and doped silicon devices. This research puts its focus on spin drift and diffusion in silicon. An analytic model for spin transport in pure silicon is analysed. Some physical phenomena discovered in experiments are analyzed and incorporated in the model. In addition, a Monte Carlo model is also built for doped silicon spin transport devices by carefully calculating the electric field distribution and electron mobility within the transit layer. A comparison between experimental data and simulation results have been made, showing a good consistency.

Spin Injection and Transport in Semiconductor and Metal Nanostructures

Author : Lei Zhu
Publisher :
ISBN 13 :
Total Pages : 127 pages
Book Rating : 4.:/5 (471 download)

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Book Synopsis Spin Injection and Transport in Semiconductor and Metal Nanostructures by : Lei Zhu

Download or read book Spin Injection and Transport in Semiconductor and Metal Nanostructures written by Lei Zhu and published by . This book was released on 2009 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we investigate spin injection and transport in semiconductor and metal nanostructures. To overcome the limitation imposed by the low efficiency of spin injection and extraction and strict requirements for retention of spin polarization within the semiconductor, novel device structures with additional logic functionality and optimized device performance have been developed. Weak localization/antilocalization measurements and analysis are used to assess the influence of surface treatments on elastic, inelastic and spin-orbit scatterings during the electron transport within the two-dimensional electron layer at the InAs surface. Furthermore, we have used spin-valve and scanned probe microscopy measurements to investigate the influence of sulfur-based surface treatments and electrically insulating barrier layers on spin injection into, and spin transport within, the two-dimensional electron layer at the surface of p-type InAs. We also demonstrate and analyze a three-terminal, all-electrical spintronic switching device, combining charge current cancellation by appropriate device biasing and ballistic electron transport. The device yields a robust, electrically amplified spin-dependent current signal despite modest efficiency in electrical injection of spin-polarized electrons. Detailed analyses provide insight into the advantages of ballistic, as opposed to diffusive, transport in device operation, as well as scalability to smaller dimensions, and allow us to eliminate the possibility of phenomena unrelated to spin transport contributing to the observed device functionality. The influence of the device geometry on magnetoresistance of nanoscale spin-valve structures is also demonstrated and discussed. Shortcomings of the simplified one-dimensional spin diffusion model for spin valve are elucidated, with comparison of the thickness and the spin diffusion length in the nonmagnetic channel as the criterion for validity of the 1D model. Our work contributes directly to the realization of spin valve and spin transistor devices based on III-V semiconductors, and offers new opportunities to engineer the behavior of spintronic devices at the nanoscale.

Handbook of Spintronics

Author : Yongbing Xu
Publisher : Springer
ISBN 13 : 9789400768918
Total Pages : 0 pages
Book Rating : 4.7/5 (689 download)

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Book Synopsis Handbook of Spintronics by : Yongbing Xu

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.

Spin Transport in Semiconductors Manipulated by Extrinsic Factors

Author : Lan Qing
Publisher :
ISBN 13 :
Total Pages : 141 pages
Book Rating : 4.:/5 (96 download)

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Book Synopsis Spin Transport in Semiconductors Manipulated by Extrinsic Factors by : Lan Qing

Download or read book Spin Transport in Semiconductors Manipulated by Extrinsic Factors written by Lan Qing and published by . This book was released on 2015 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Spin transport in semiconductors is of fundamental research interest not only for addressing basic solid state physics aspects, but also for the already demonstrated potential it has in electronic and storage technologies. The centerpiece of spin-dependent transport focuses on the spin relaxation. So far, spin lifetimes deduced from many spin transport measurements indicate certain discrepancies with the theoretical values developed from intrinsic electron-phonon interactions in equilibrium. Detailed investigation for each of the experiments is needed in order to fill the gap, and here we show how these spin transports in semiconductors can be manipulated by extrinsic factors, such as external field, doping-induced exchange, and device structure. The comprehensive consideration of all these influences results in a consistent agreement between theory and experiment, as well as a transparent physical picture. Electric fields can drive electrons away from thermal equilibrium and substantially enhance the dominant spin relaxation mechanism in silicon and germanium. Empirical results from spin transport devices with ballistic injection confirms our theory for such strong spin depolarization. It enables the optimization of spintronics devices, as we can choose the electric field that optimizes the tradeoff between fast transport across the device and signal loss due to spin depolarization. The scenario is more promising when applying strainches Meanwhile, at low temperatures conduction electrons accelerated by electric fields can also excite the localized electrons frozen at the doped impurities via inelastic scattering. Promotion into highly spin-mixed localized states leads to spin depolarization that couples strongly to the conduction electrons by exchange interaction. This novel spin relaxation mechanism is a key ingredient when one tries to model the anomalous behaviors observed at low temperatures. The exchange between conduction and localized electrons can play an important role as well in electrical Hanle effect measurement. A unique Lorentzian-shaped signal is discovered in both theory and experiment. Its shape does not directly relate to spin relaxation as commonly believed. This effect together with the briefly discussed impurity-assisted tunneling magnetoresistance elucidates the reliability of the spin lifetime extracted from a three-terminal device geometry. The spin dynamics with extrinsic factors developed in this thesis possesses broad applications. We show two practical cases in optical orientation that exhibit an outlook beyond spin transport. The examined evolutions of hot electrons and the corresponding spin properties reveal the underlying physics of crystal symmetry and band structures. The method can be further utilized to complete the picture of spin relaxation in semiconductors, and to analyze the extrinsic spin Hall effect"--Pages viii-ix.

Organic Spintronics

Author : Zeev Valy Vardeny
Publisher : CRC Press
ISBN 13 : 1439806578
Total Pages : 354 pages
Book Rating : 4.4/5 (398 download)

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Book Synopsis Organic Spintronics by : Zeev Valy Vardeny

Download or read book Organic Spintronics written by Zeev Valy Vardeny and published by CRC Press. This book was released on 2010-04-09 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Major development efforts in organic materials research has grown for an array of applications. Organic spintronics, in particular, has flourished in the area of organic magneto-transport. Reflecting the main avenues of advancement in this arena, this volume explores spin injection and manipulation in organic spin valves, the magnetic field effect in organic light-emitting diodes (OLEDs), the spin transport effect in relation to spin manipulation, organic magnets as spin injection electrodes in organic spintronics devices, the coherent control of spins in organic devices using the technique of electronically detected magnetic resonance, and the possibility of using organic spin valves as sensors.