Download or read book Nanomagnetic and Spintronic Devices for Energy Efficient Memory and Computing written by Jayasimha Atulasimha and published by John Wiley & Sons. This book was released on 2016-02-03 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomagnetic and spintronic computing devices are strong contenders for future replacements of CMOS. This is an important and rapidly evolving area with the semiconductor industry investing significantly in the study of nanomagnetic phenomena and in developing strategies to pinpoint and regulate nanomagnetic reliably with a high degree of energy efficiency. This timely book explores the recent and on-going research into nanomagnetic-based technology. Key features: Detailed background material and comprehensive descriptions of the current state-of-the-art research on each topic. Focuses on direct applications to devices that have potential to replace CMOS devices for computing applications such as memory, logic and higher order information processing. Discusses spin-based devices where the spin degree of freedom of charge carriers are exploited for device operation and ultimately information processing. Describes magnet switching methodologies to minimize energy dissipation. Comprehensive bibliographies included for each chapter enabling readers to conduct further research in this field. Written by internationally recognized experts, this book provides an overview of a rapidly burgeoning field for electronic device engineers, field-based applied physicists, material scientists and nanotechnologists. Furthermore, its clear and concise form equips readers with the basic understanding required to comprehend the present stage of development and to be able to contribute to future development. Nanomagnetic and Spintronic Devices for Energy-Efficient Memory and Computing is also an indispensable resource for students and researchers interested in computer hardware, device physics and circuits design.

Download or read book Nanomagnetic and Spintronic Devices for Energy Efficient Memory and Computing written by Jayasimha Atulasimha and published by John Wiley & Sons. This book was released on 2016-01-27 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomagnetic and spintronic computing devices are strong contenders for future replacements of CMOS. This is an important and rapidly evolving area with the semiconductor industry investing significantly in the study of nanomagnetic phenomena and in developing strategies to pinpoint and regulate nanomagnetic reliably with a high degree of energy efficiency. This timely book explores the recent and on-going research into nanomagnetic-based technology. Key features: Detailed background material and comprehensive descriptions of the current state-of-the-art research on each topic. Focuses on direct applications to devices that have potential to replace CMOS devices for computing applications such as memory, logic and higher order information processing. Discusses spin-based devices where the spin degree of freedom of charge carriers are exploited for device operation and ultimately information processing. Describes magnet switching methodologies to minimize energy dissipation. Comprehensive bibliographies included for each chapter enabling readers to conduct further research in this field. Written by internationally recognized experts, this book provides an overview of a rapidly burgeoning field for electronic device engineers, field-based applied physicists, material scientists and nanotechnologists. Furthermore, its clear and concise form equips readers with the basic understanding required to comprehend the present stage of development and to be able to contribute to future development. Nanomagnetic and Spintronic Devices for Energy-Efficient Memory and Computing is also an indispensable resource for students and researchers interested in computer hardware, device physics and circuits design.

Download or read book Energy Efficient Spintronic Device for Neuromorphic Computation written by Md Ali Azam and published by . This book was released on 2019 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Future computing will require significant development in new computing device paradigms. This is motivated by CMOS devices reaching their technological limits, the need for non-Von Neumann architectures as well as the energy constraints of wearable technologies and embedded processors. The first device proposal, an energy-efficient voltage-controlled domain wall device for implementing an artificial neuron and synapse is analyzed using micromagnetic modeling. By controlling the domain wall motion utilizing spin transfer or spin orbit torques in association with voltage generated strain control of perpendicular magnetic anisotropy in the presence of Dzyaloshinskii-Moriya interaction (DMI), different positions of the domain wall are realized in the free layer of a magnetic tunnel junction to program different synaptic weights. Additionally, an artificial neuron can be realized by combining this DW device with a CMOS buffer. The second neuromorphic device proposal is inspired by the brain. Membrane potential of many neurons oscillate in a subthreshold damped fashion and fire when excited by an input frequency that nearly equals their Eigen frequency. We investigate theoretical implementation of such "resonate-and-fire" neurons by utilizing the magnetization dynamics of a fixed magnetic skyrmion based free layer of a magnetic tunnel junction (MTJ). Voltage control of magnetic anisotropy or voltage generated strain results in expansion and shrinking of a skyrmion core that mimics the subthreshold oscillation. Finally, we show that such resonate and fire neurons have potential application in coupled nanomagnetic oscillator based associative memory arrays.

Download or read book Spintronics Based Neuromorphic Computing written by Debanjan Bhowmik and published by Springer Nature. This book was released on with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Magnetic Domain Wall Devices written by Saima Afroz Siddiqui and published by . This book was released on 2019 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spintronics promises intriguing device paradigms where electron spin is used as the information token instead of its charge counterpart. Spin transfer torque-magnetic random access memory (STT-MRAM) is considered one of the most mature nonvolatile memory technologies for next generation computers. Spin based devices show promises also for beyond-CMOS, in memory computing and neuromorphic accelerators. In the future cognitive era, nonvolatile memories hold the key to solve the bottleneck in the computational performance due to data shuttling between the processing and the memory units. The application of spintronic devices for these purposes requires versatile, scalable device design that is adaptable to emerging material physics. We design, model and experimentally demonstrate spin orbit torque induced magnetic domain wall devices as the building blocks (i.e. linear synaptic weight generator and the nonlinear activation function generator) for in-memory computing, in particular for artificial neural networks. Spin orbit torque driven magnetic tunnel junctions show great promise as energy efficient emerging nonvolatile logic and memory devices. In addition to its energy efficiency, we take advantage of the spin orbit torque induced domain wall motion in magnetic nanowires to demonstrate the linear change in resistances of the synaptic devices. Modifying the spin-orbit torque from a heavy metal or utilizing the size dependent magnetoresistance of tunnel junctions, we also demonstrate a nonlinear activation function for thresholding signals (analog or digitized) between layers for deep learning. The analog modulation of resistances in these devices requires characterizing the resolution of the resistance. Since domain wall in magnetic wires is the nonvolatile data token for these devices, we study the spatial resolution of discrete magnetic domain wall positions in nanowires. The studies on domain wall is further extended to identify energy-efficient and dynamically robust superior magnetic material for ultra-fast and efficient devices for neuromorphic accelerators.

Download or read book Energy efficient and Secure Designs of Spintronic Memory written by Anirudh Iyengar and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With increased integration of technology in our lives, the arms race between chip manufacturers to provide the latest and greatest to entice the consumer, only intensifies. A by-product of this growth is an ever-increasing demand for performance and efficiency. To address this problem CMOS transistors have always been scaled to smaller nodes to fit in more functionality as well as lower the overall energy-footprint of the operation. However, scaling down the size of the transistor is becoming difficult, which in-turn dramatically reduces the profit motive of such an endeavor. Additionally, several new challenges are emerging in integrated circuit (IC) design: mainly leakage power (in caches) and the need for high-bandwidth computing. With this foresight, the industry began investigating alternative memory technologies such as: Resistive RAM (RRAM), Phase Change RAM (PCRAM), Spin Transfer Torque RAM (STTRAM), Domain Wall Memory (DWM), Magnetic RAM (MRAM), Ferroelectric RAM (FeRAM), Memristor etc., that could replace CMOS in cache applications whilst providing non-volatility (to eradicate leakage), high-density (high-bandwidth compute) and high-endurance (long lifetime). A side-effect of incorporating these new memory technologies is the issue of security, privacy and counterfeiting. As the demand for technology increases, the motivation for adversaries to tamper with them for economic, political and social gains will only increase.A major perspective for the beyond CMOS comes from spintronic memory (as per the International Technology Roadmap for Semiconductors) exploiting not only the charge of electrons but more importantly their magnetism, or their spin. STTRAM and DWM offer much potential owing to their high endurance, retention and density while operating at low-voltages. This motivated me to explore various possibilities of spintronic memory (STTRAM and DWM) in the domain of energy-efficiency, security and testing. This thesis addresses: (i) energy-efficient applications and techniques for a system employing spintronic memory; (ii) the security challenges we might face adopting spintronic memory; and (iii) the need for securing traditional CMOS ICs from a counterfeiting as well as a duplication standpoint. In particular, we tackle the problems in energy-efficiency, authentication, privacy and secrecy. The first part of the thesis describes the modeling aspects of spintronic memory i.e. STTRAM and DWM. Then, we present three energy-efficient spintronic memory applications: (i) non-volatile flip-flop (NVFF), (ii) MTJ crossbar using selector diode (SD) and, (iii) pulsed shifting of DWs. Apart from the traditional state retentivity, the proposed NVFF offers protection against unexpected power-cuts allowing for a fluid instant-ON experience. The MTJ crossbar using a MIIM SD allows for a high-density design with the necessary robustness and energy-efficiency demanded by high bandwidth applications. The pulsed shifting technique of DWs reduces the impact of Joule heating in NWs, thus, maintaining energy efficiency without sacrificing performance. In the next part of the thesis we present potential security vulnerabilities side channel analysis and data privacy, of STTRAM and DWM. We present some mitigation techniques to circumvent these issues. Following this, we explore the security aspects of said spintronic memory, by illustrating their potential use as a PUF. Our proposed PUFs exploit the inherently large entropy surrounding the DW NW making them a strong candidate for magnetic memory-based authentication. We then analyze the operation and robustness of the PUFs under varying supply and temperature conditions.Finally, we describe threshold voltage defined CMOS switches for camouflaging logic. By modifying the doping concentration of selective CMOS switches at design-time, we have been able to realize six different logic functionalities. We demonstrate the designs by implementing ring oscillators (RO) in a 65nm node test-chip on which we analyze the impact of supply-voltage, process variation and temperature. Also, we demonstrate how we can reclaim lost performance by tuning the gate voltage under varying temperatures and supply voltages. The difficulty in RE the netlist when a portion of the gates are camouflaged gate is quantified by estimating the time taken for the decamouflaging process. We also describe camouflaged gate selection using controllability and observability conditions. Additionally, an alternative camouflaging technique that operates on charge-trap is described. The advantage of this technique is that the charge trapped in the gate oxide is responsible for gate selection, thus leaving no physical evidence of camouflaging.In summary, this dissertation provides an overview of the design, analysis and applications of STTRAM and DWM for energy-efficiency and enhanced device security.

Download or read book Spintronics based Computing written by Weisheng Zhao and published by Springer. This book was released on 2015-05-11 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive introduction to spintronics-based computing for the next generation of ultra-low power/highly reliable logic. It will cover aspects from device to system-level, including magnetic memory cells, device modeling, hybrid circuit structure, design methodology, CAD tools, and technological integration methods. This book is accessible to a variety of readers and little or no background in magnetism and spin electronics are required to understand its content. The multidisciplinary team of expert authors from circuits, devices, computer architecture, CAD and system design reveal to readers the potential of spintronics nanodevices to reduce power consumption, improve reliability and enable new functionality.

Download or read book Magnetic Memory with Topological Insulators and Ferrimagnetic Insulators written by Qiming Shao and published by . This book was released on 2019 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ubiquitous smart devices and internet of things create tremendous data every day, shifting computing diagram towards data-driven. Computing and memory units in traditional computers are physically separated, which leads to huge energy cost and time delay. Novel computer architectures bring computing and memory units together for data-intensive applications. These memory units need to be fast, energy efficient, scalable and nonvolatile. This dissertation concerns innovating new types of magnetic memory or spintronic devices to achieve ultrahigh energy efficiency and ultracompact size from a perspective of material and heterostructure design. Especially, we employ quantum materials to enable potentially unprecedented technological advances. The highest energy efficiency of magnetic memory requires the largest charge-to-spin conversion efficiency that allows the minimum power to manipulate the magnetization. We utilize topological surface states of topological insulators (TIs), which have unique spin-momentum locking and thus are highly spin-polarized. We discover giant spin-orbit torques (SOTs) from TIs at room temperature, which are more than one order of magnitude larger than those of traditional heavy metals. We integrate TIs into room temperature magnetic memories, which promises future ultralow power dissipation. SOT characterization methods and related SOT studies on heavy metals, monolayer two-dimensional materials, and magnetic insulators-based heterostructures are discussed in detail. To have the best scaling performance, we investigate emerging topological skyrmions in magnetic thin films, which are arguably the smallest spin texture in nature. While most of the skyrmions are discovered in metallic systems, insulating skyrmions are desired thanks to their lower damping and thus potentially lower power dissipation. We observe high-temperature electronic signatures of skyrmions in magnetic insulators, topological Hall effect, by engineering heterostructures consisting of heavy metals and magnetic insulators. This new platform is essential for exploring fundamental magnon-skyrmion physics and pursuing practical applications based on insulating skyrmions. To have the highest operation speed, we explore compensated ferrimagnetic insulators, which have THz dynamics due to the strong exchange coupling field. We realize energy efficient switching of the ferrimagnetic insulator in both ferrimagnetic and antiferromagnetic states, promising electrical manipulation of ultrafast dynamics.

Download or read book Advanced Luminescent Materials and Quantum Confinement written by M. Cahay and published by The Electrochemical Society. This book was released on 1999 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Emerging Non volatile Memory Technologies written by Wen Siang Lew and published by Springer Nature. This book was released on 2021-01-09 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a balanced and comprehensive guide to the core principles, fundamental properties, experimental approaches, and state-of-the-art applications of two major groups of emerging non-volatile memory technologies, i.e. spintronics-based devices as well as resistive switching devices, also known as Resistive Random Access Memory (RRAM). The first section presents different types of spintronic-based devices, i.e. magnetic tunnel junction (MTJ), domain wall, and skyrmion memory devices. This section describes how their developments have led to various promising applications, such as microwave oscillators, detectors, magnetic logic, and neuromorphic engineered systems. In the second half of the book, the underlying device physics supported by different experimental observations and modelling of RRAM devices are presented with memory array level implementation. An insight into RRAM desired properties as synaptic element in neuromorphic computing platforms from material and algorithms viewpoint is also discussed with specific example in automatic sound classification framework.

Download or read book Introduction to Spintronics written by Supriyo Bandyopadhyay and published by CRC Press. This book was released on 2008-03-20 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using spin to replace or augment the role of charge in signal processing devices, computing systems and circuits may improve speed, power consumption, and device density in some cases—making the study of spinone of the fastest-growing areas in micro- and nanoelectronics. With most of the literature on the subject still highly advanced and heavily theoretical, the demand for a practical introduction to the concepts relating to spin has only now been filled. Explains effects such as giant magnetoresistance, the subject of the 2007 Nobel Prize in physics Introduction to Spintronics is an accessible, organized, and progressive presentation of the quantum mechanical concept of spin. The authors build a foundation of principles and equations underlying the physics, transport, and dynamics of spin in solid state systems. They explain the use of spin for encoding qubits in quantum logic processors; clarify how spin-orbit interaction forms the basis for certain spin-based devices such as spintronic field effect transistors; and discuss the effects of magnetic fields on spin-based device performance. Covers active hybrid spintronic devices, monolithic spintronic devices, passive spintronic devices, and devices based on the giant magnetoresistance effect The final chapters introduce the burgeoning field of spin-based reversible logic gates, spintronic embodiments of quantum computers, and other topics in quantum mechanics that have applications in spintronics. An Introduction to Spintronics provides the knowledge and understanding of the field needed to conduct independent research in spintronics.

Download or read book McGraw Hill Yearbook of Science and Technology 2010 written by McGraw-Hill Education and published by McGraw Hill Professional. This book was released on 2010-01-12 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes coverage of forefront fields such as cell and molecular biology, environmental science, genetics, information technology, nanotechnology, chemistry, and theoretical physics An extensive subject index makes finding information fast and easy Features numerous cross-references to the McGraw-Hill Encyclopedia of Science & Technology and bibliographies of key literature after each article 250+ images, diagrams, and tables enhance the text

Download or read book Ultrafast Manipulation of Magnetization Using On chip THz written by Kaushalya and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for memory storage devices has skyrocketed over the last few decades especially after the development of the internet. This need has reached enormous heights in the past two years, soon after the pandemic due to COVID-19. Hard disk drives (HDDs) are known to have the potential to meet up with the high-density data storage demands. This thesis deals with one of the major challenges faced within the spintronic community to improve the speed and the energy consumption of memory devices.The speed of operation during the writing of a magnetic bit depends on the magnetization switching mechanism employed. The switching mechanism is itself dependent on the intrinsic magnetic properties of the sample and the externally induced excitation that drives the reversal of the magnetic bit 1. In this thesis, we will focus on the use of spin-orbit torque (SOT) excitations to drive the reversal, which is a relatively new but fast and energy-efficient approach in comparison with other state-of-the-art methods.The typical speed of magnetization reversal using SOTs is in the range of few nanoseconds, far slower than the picosecond-long switching that is possible with charge-based memory devices2. In fact, a record reversal speed with electrical pulses as short as ~200ps was reported by Garello et. al., 3 in 2011 using SOTs. This thesis reports further efforts to speed up the magnetization reversal by almost 2 orders of magnitude by exploiting such SOTs. To this aim, THz electrical pulses were generated via the use Auston photoconductive switches. We demonstrate that a single 6ps wide electrical pulse can induce a SOT to a 1nm thin Co ferromagnetic layer and result in a full magnetization reversal. A systematic study to understand SOTs in the picosecond time regime is also undertaken via using different magnetic nanostructures.In magnetic memory devices, a “read-head” is used to read the stored information in the device. Typically, in spintronic devices, giant magnetoresistance (GMR) or tunnel magnetoresistance (TMR) based read heads are used for such operations. In this thesis, we also report on the attempts of developing a GMR sensor working in the THz regime.To undertake the aforementioned studies, a pump-probe optical and optoelectrical experimental setup has also been built and a detailed report of the same is also provided in the thesis.

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 Electrostatic Kinetic Energy Harvesting written by Philippe Basset and published by John Wiley & Sons. This book was released on 2016-03-28 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Harvesting kinetic energy is a good opportunity to power wireless sensor in a vibratory environment. Besides classical methods based on electromagnetic and piezoelectric mechanisms, electrostatic transduction has a great perspective in particular when dealing with small devices based on MEMS technology. This book describes in detail the principle of such capacitive Kinetic Energy Harvesters based on a spring-mass system. Specific points related to the design and operation of kinetic energy harvesters (KEHs) with a capacitive interface are presented in detail: advanced studies on their nonlinear features, typical conditioning circuits and practical MEMS fabrication.

Download or read book Nanomagnetism and Spintronics written by Farzad Nasirpouri and published by World Scientific. This book was released on 2011 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomagnetism and spintronics are two close subfields of nanoscience, explaining the effect of substantial magnetic properties of matter when the materials fabrication is realized at a comparable length size. Nanomagnetism deals with the magnetic phenomena specific to the structures having dimensions in the submicron range. The fact that the electronic transport properties of materials are dependent on the magnetic properties' artificial nanostructures, i.e., giant magnetoresistance (GMR) or tunneling magnetoresistance (TMR), has revolutionized spintronics science and technology. This book explains the concepts of nanomagnetism and spintronics by viewing the most recent research works from internationally distinguished research groups. Placing special emphasis on crucial fundamental and technical aspects of nanomagnetism and spintronics, it serves as a one-stop reference for universities offering postgraduate programs in nanotechnology or related disciplines. This unique book deals with all three stages required for conducting research in nanomagnetism and spintronics including fabrication, characterization and applications of nanomagnetic and spintronics materials, providing general concepts and an insightful overview of this subject for research students and scientists from different backgrounds investigating the multidisciplinary area of nanotechnology.

Download or read book Developments in Data Storage written by S. N. Piramanayagam and published by John Wiley & Sons. This book was released on 2011-10-11 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: A timely text on the recent developments in data storage, from a materials perspective Ever-increasing amounts of data storage on hard disk have been made possible largely due to the immense technological advances in the field of data storage materials. Developments in Data Storage: Materials Perspective covers the recent progress and developments in recording technologies, including the emerging non-volatile memory, which could potentially become storage technologies of the future. Featuring contributions from experts around the globe, this book provides engineers and graduate students in materials science and electrical engineering a solid foundation for grasping the subject. The book begins with the basics of magnetism and recording technology, setting the stage for the following chapters on existing methods and related research topics. These chapters focus on perpendicular recording media to underscore the current trend of hard disk media; read sensors, with descriptions of their fundamental principles and challenges; and write head, which addresses the advanced concepts for writing data in magnetic recording. Two chapters are devoted to the highly challenging area in hard disk drives of tribology, which deals with reliability, corrosion, and wear-resistance of the head and media. Next, the book provides an overview of the emerging technologies, such as heat-assisted magnetic recording and bit-patterned media recording. Non-volatile memory has emerged as a promising alternative storage option for certain device applications; two chapters are dedicated to non-volatile memory technologies such as the phase-change and the magnetic random access memories. With a strong focus on the fundamentals along with an overview of research topics, Developments in Data Storage is an ideal reference for graduate students or beginners in the field of magnetic recording. It also serves as an invaluable reference for future storage technologies including non-volatile memories.