Download or read book In situ Magnetoresistance Measurements During Patterning of Spin Valve Devices written by Deborah Morecroft and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes an experimental study on the patterning of thin films and spinvalve devices. Initially the change in the magnetisation reversal of ferromagneticNi80Fe15Mo5 thin films was investigated as the shape anisotropy was increased using opticallithography to pattern wire arrays. These structures show a progressive increase in coercivityand a transition between single and two-stage reversal with increasing milling depth. Asimilar patterning technique was applied to unpinned (Ni80Fe20/Cu/Ni80Fe20) pseudo spinvalve (PSV) structures in order to enhance the coercivity of one of the ferromagnetic layers. The increased coercivity induced by micropatterning changed the natural similarity of themagnetic layers and the structure exhibited a small spin valve response. These initialmeasurements were carried out with separate milling and electrical characterisation steps. However, it was decided that it would be ideal to design a technique to do in-situmagnetoresistance measurements during milling. This meant that the samples could be milledand characterised in the same step, leading to a much cleaner and more efficient process. In-situ magnetoresistance measurements were carried out during micropatterning of PSVdevices, and the measurements showed the evolution in the electrical response as wirestructures were gradually milled through the thickness. Contrary to what was expected, thestructures showed a maximum spin valve response when fully milled through. The effect offurther increasing the shape anisotropy by reducing the wire width, and changing the materialproperties in the PSV structure has also been investigated. MR measurements were taken asthe temperature was increased from 291K to 493K, and the results show that the patternedPSV structures have a better thermal stability than exchange biased spin valves with an IrMnpinning layer. The experiment was extended to the nanoscale, and the results show that a significant increasein MR is not observed despite the fact that the magnetic configuration tends more towardssingle domain. This is thought to be due to an increase in the initial resistance of thestructures. A small increase in MR was observed as the wire width was decreased from 730 to470nm, although the spin valve response is heavily dependent on the gallium dosage densityduring patterning in the Focused Ion Beam (FIB). Micromagnetic simulations were carriedout, which agree with the experimental results and showed the change in the magnetisationreversal from rotation to switching as the dimensions were reduced on the nanoscale.
Download or read book Magnetoresistance of mesoscopic metallic spin valve devices written by Alexander van Staa and published by Cuvillier Verlag. This book was released on 2006-08-29 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spin-polarized transport in all-metal spin-valve devices consisting of two bar-shaped permalloy electrodes and an interconnecting aluminum strip are studied in this thesis. Two different geometries are realized: one has a planar aluminum strip, the other has planar permalloy electrodes. The anisotropic magnetoresistance of the electrodes and the magnetoresistance of the entire device are measured in the same cooling cycles at liquid helium temperatures and above. The mesoscopic spin-valve effect is observed in samples with both layouts. The spin-valve effect can be clearly distinguished from parasitic effects, namely the anisotropic magnetoresistance and the local Hall effect. The magnitude of the spin-valve effect and its temperature dependence show good agreement with a theoretical estimation based on diffusive transport. The micromagnetic behavior of the permalloy electrodes is explored with a magnetic-force microscope at room temperature and with measurements of the anisotropic magnetoresistance at low temperatures. Tunnel barriers at the interfaces between the ferromagnets and the normal metal are predicted to increase the spin-injection efficiency. Therefore, the natural oxidation of aluminum in pure oxygen is studied with non-magnetic tunnel junctions. Aluminum oxide tunnel barriers are fabricated successfully both in an evaporation chamber and in a multi-target sputter-deposition system. The latter enables the in situ fabrication of high quality interfaces with aluminum oxide tunnel barriers.
Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2004 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Novel Magnetoresistance Effects in Microstructured Metal semiconductor Hybrid Structures Fabricated by Cleaved edge Overgrowth written by Claas Henrik Möller and published by Cuvillier Verlag. This book was released on 2004 with total page 122 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 Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Giant Magneto Resistance Devices written by E. Hirota and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is one of the first application-orientated books on the subject. The main topics are magnetic sensors with high resolutions and magnetic read heads with high sensitivities, required for hard-disk drives with recording densities of several gigabytes. Another important subject is novel magnetic random-access memory (MRAM) with non-volatile non-destructive and radiation-hard characteristics.
Download or read book Theoretical and Technological Advancements in Nanotechnology and Molecular Computation Interdisciplinary Gains written by MacLennan, Bruce and published by IGI Global. This book was released on 2010-11-30 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical and Technological Advancements in Nanotechnology and Molecular Computation: Interdisciplinary Gains compiles research in areas where nanoscience and computer science meet. This book explores current and future trends that discus areas such as, cellular nanocomputers, DNA self-assembly, and the architectural design of a "nano-brain." The authors of each chapter have provided in-depth insight into the current state of research in nanotechnology and molecular computation as well as identified successful approaches, tools and methodologies in their research.
Download or read book Exchange Biased and Closed flux Pseudo Spin valve Materials Device Applications and Electrical Reliability written by Seongtae Bae and published by . This book was released on 2003 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2726 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Official Gazette of the United States Patent and Trademark Office written by and published by . This book was released on 1999 with total page 758 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics of Ultra High Density Magnetic Recording written by M.L. Plumer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Application-oriented book on magnetic recording, focussing on the underlying physical mechanisms that play crucial roles in medium and transducer development for high areal density disk drives.
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 High Sensitivity Magnetometers written by Asaf Grosz and published by Springer. This book was released on 2016-09-20 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers, for the first time, an overview of nearly all of the magnetic sensors that exist today. The book is offering the readers a thorough and comprehensive knowledge from basics to state-of-the-art and is therefore suitable for both beginners and experts. From the more common and popular AMR magnetometers and up to the recently developed NV center magnetometers, each chapter is describing a specific type of sensor and providing all the information that is necessary to understand the magnetometer behavior including theoretical background, noise model, materials, electronics, design and fabrication techniques, etc.
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 Spin Electronics written by Michael Ziese and published by Springer. This book was released on 2007-06-30 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: For 50 years conventional electronics has ignored the electron spin. The manipulation and utilisation of the electron spin heralds an exciting and rapidly changing era in electronics, combining the disciplines of magnetism and traditional electronics. The first generation of "spintronic" devices (such as read heads based on giant magnetoresistance or non-volatile magnetic random access memories) have already gained dominant positions in the market place. This volume, the first of its kind on spin electronics describes all the essential topics for new researchers entering the field. It covers magnetism and semiconductor basics, micromagnetism, experimental techniques, materials science, device fabrication and new developments in spin-dependent processes. At the end of most chapters are a number of exercises and worked problems to aid the reader in understanding this fascinating new field.
