Second harmonic detection of spin dependent transport in magnetic nanostructures article pdf available in chinese physics letters 272 february 2010 with 39 reads how we measure reads. Unlike in spin valves, the current flows through the junction perpendicular to the layers fig. Spin dependent transport and spin transfer in nanoconstrictions and current confined nanomagnets ozhan ozatay, ph. It may enhance the transport of spin up electrons, and improve sf. Handbook of spin transport and magnetism provides a comprehensive, balanced account of the state of the art in. Then, chapter 7 discusses weakly disordered 9780521877480 transport in nanostructures, second edition. It is shown that, only in the nanostructures with symmetric magnetic field with respect to the magnetic modulation direction, electrons exhibit a considerable. The discovery of gmr triggered an extensive research effort on spin transport in magnetic nanostructures. We use these strayfield effects for detailed studies on the magnetic properties of rectangular micromagnets, nanodisks and nanorings. The complexity associated with the classical quantum.
This page intentionally left blank transport in nanostructures second edition providing a muchneeded update on the l. Spin transport in magnetic nanostructures how is spin transport in magnetic nanostructures abbreviated. Spindependent quantum interference within a single. Especially interesting are recently discovered twodimensional magnetic vdw materials, providing new paradigms for spintronic applications. I will introduce this method in the following chapter. Bennemann encyclopedia of life support systems eolss note, in nanostructured thin films magnetic domain structure is frequently present and the reversal of a domain magnetization may be relatively slow. When confined to magnetic nanostructures, an imbalance between electrons of opposite spin orientations leads to spin polarized electron waves, giving rise to spin dependent quantum interference. Spinorbit induced dynamics in multilayer nanostructures.
Introduction magnetization switching processes and spin dynamics in general are fundamental issues in magnetism, and are essential to technological applications such as magnetic storage and spintronics 1,2. Magnetic nanostructures 1 emil burzo magnetic nanostructures. Cornell university 2007 in this thesis, i have employed point contact spectroscopy to determine the nature of electron transport across constrained domain walls in a ferromagnetic nanocon. Together, gmr and stt are at the foundation of numerous technologies, and they hold promise. Firstprinciples study of spindependent transport through. Spindependent transport through magnetic nanojunctions.
The discovery of gmr triggered an extensiv e research effort on spin transport in magnetic nanostructures. Functional approximation for the spin dependent quantum transport in magnetic nanostructures aip conference. We study the spindependent transport properties of the nanostructures consisting of realistic magnetic barriers produced by the deposition of ferromagnetic stripes on heterostructures. The enhancement is also expected in semiconductor devices. The magnetic thin films and multilayers can be considered as nanostructures 23. Spinpolarized transport in ferromagnetic multilayered. Spintransport and transfer basics giant magnetoresistance gmr spin filtering and spin momentum transfer ii. Spindependent transport through a quantum wire with. Spin dependent transport in magnetic nanostructures advances.
This book introduces and explains the basic physics and applications of a variety of spindependent transport phenomena in magnetic nanostructures with particular emphasis on magnetic multilayers and. Coherent electronic transport through a molecular device is studied using non equilibrium greens function negf formalism. Spin dependent transport in magnetic nanostructures pdf. Spindependent tunneling in nanostructures consisting of. This resource letter provides a guide to the literature in the still rapidly developing area of spindependent transport phenomena, which forms the basis for applications in magnetoelectronics. The focus upon single electron tunneling remains, but considerable new material on coupled dots has been added. The nanostructures we study are triangular co islands located on a nonmagnetic. The dependence of magnetic spin and orbital moments and spin correlations on particle size and temperature are of interest. Chapter 6 focuses upon quantum dots with new material on the role of spin. Remaining sections are devoted to transport studies on double quantum dot. Spin injection and nonlocal spin transport in magnetic. Spin dependent transport in magnetic nanostructures crc press. Features of the current spinorbit induced magnetic dynamics in multilayer nanostructures with nonmagnetic heavy metal layers possessing by a strong spinorbit interaction are studied.
An important focus of the group focus lies in the investigation of the electronic and magnetic properties of nanostructures at surfaces. Spindependent schottky barriers and vacancyinduced spin. Elsevier journal of magnetism and magnetic materials 156 1996 315316 invited paper iii journal of magnetism and magnetic materials spin dependent transport in magnetic nanostructures s. Thermal spin injection describes the injection of spins in a nonmagnetic. You will use quantumatk to study the colinear and noncolinear spindependent transport properties, including electronic transmission, tunnel magnetoresistance, and spintransfer torque. Surface roughness is known to be an important source of scattering in small structures.
We discuss spindependent electron spill out and demonstrate in a combined theoretical and experimental work that compelling consequences for spinpolarization and spindependent transport arise at the edges of magnetic nanostructures due to the spindependent smoluchowski. The 2nd gordon research conference and 1st gordon research seminar on spin dynamics in nanostructures will provide an important stage for the main players in the field and those who want to joint them to present and discuss new results and future plans, in. We study theoretically the spin transport in a nonmagnetic metal connected to ferromagnetic injector and detector electrodes. When two magnetic dots are embedded in a nanowire, the single electron tunneling process may be controlled by the magnetic field. Enhanced magnetic field sensitivity of spindependent. Currentinduced magnetization switching cims due to spintransfer torques is an advanced switching concept for magnetic nanostructures in spintronic devices. Two of the principal phenomena observed and exploited in the field of spintronics are giant magnetoresistance gmr and spin transfer torque stt. Such device is made of atomic nanowire which is connected to ferromagnetic electrodes. In summary, these are some cluster like nanostructures. The 2nd gordon research conference and 1st gordon research seminar on spin dynamics in nanostructures will provide an important stage for the main players in the field and those who want to joint them to present and discuss new results and future plans, in theory, computation, simulation, and experiments.
The spin asymmetry of schottky barriers may result in different tunneling rates of spin up and down electrons, and then lead to spin polarized current, namely spin filter sf effect. Special attention is paid to the spin accumulation and spin current caused by spin injection into non magnetic metals and semiconductors and superconductors. Spin transport in magnetic nanostructures how is spin. It neglects that electrons in addition to charge also carry a spin. Spin transport and current induced magnetization dynamics in. Nanomagnetism and spintronics is a rapidly expanding and increasingly important field of research with many applications already on the market and many more to be expected in the near. In a device containing a superconductor f1sf2, the e. Buy spin dependent transport in magnetic nanostructures advances in condensed matter science on free shipping on qualified orders. Spin dependent transport in magnetic nanostructures crc. In conclusion, we have proposed the spin blockade for the single electron tunneling. Using stateoftheart commercial and homemade density functional theory and kinetic monte carlo codes software we study, among other things, electronic properties of nanoscale surface structures, and spin dependent effects therein, to better understand. Kelly, thermoelectric effects in magnetic nanostructures.
As the graphene flake becomes small and is more isolated by the boron nitride region, the magnetic ordering of the flake increases. Read spindependent transport through a quantum wire with magnetic impurity, journal of shanghai university english edition on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. A variety of phenomena induced in nanosuperconductorferromagnet devices are proposed, examining the spincharge separation in. The magnetizations of f1 and f2 are aligned either parallel or antiparallel. Spindependent transport in magnetic nanostructures sciencedirect. Special attention is paid to the spin accumulation and spin current caused by spin injection into nonmagnetic metals and semiconductors and superconductors. The occurrence of inhomogeneous spindensity distribution in multilayered ferromagnetic diluted magnetic semiconductor nanostructures leads to strong.
Spindependent transport in antiferro and ferrimagnetic nanostructures. Elsevier journal of magnetism and magnetic materials 156 1996 315316 invited paper iii journal of magnetism and magnetic materials spindependent transport in magnetic nanostructures s. The phenomena also depend on the geometry of the devices. Spindependent transport in magnetic nanostructures. He has recently served on the aip steering cmte for magnetic materials, and as a committee member. With gmr, the resistance of a magnetic multilayer is affected by the relative orientation of its magnetic layers due to electron spin dependent scattering. Spin dependent transport in magnetic nanostructures.
This is because the spindependent tunneling between the dots are governed by the field. Cornell university 2003 this dissertation describes the development and use of a set of techniques used to fabricate magnetic nanostructures where a current can be applied perpendicular to the plane of the thin. Spinpolarized transport in magnetic nanostructures. The aim of this thesis work was to obtain a deeper understanding of spindependent transport by the study of mixed effects of heat and charge currents in magnetic nanostructures. Quantum transport in semiconductor nanostructures pdf. A dissertation submitted to the faculty of the graduate school of the university of minnesota by xi chen in partial fulfillment of the requirements for the degree of doctor of philosophy randall h. The occurrence of inhomogeneous spin density distribution in multilayered ferromagnetic diluted magnetic semiconductor nanostructures leads to strong. The dependence of magnetic spin and orbital moments and spin correlations on particle size and temperature are of. Here, using density functional theory dft calculations, we investigate the spindependent electronic transport across vdw magnetic tunnel junctions mtjs composed of fe3gete2 ferromagnetic electrodes and a graphene or hexagonal boron nitride hbn spacer layer. Regarding magnetism transition metal and rareearth atoms, metaloxydes etc. Polarized neutron reflectometry with polarization analysis is a method for depthresolved investigation of magnetic layered st ructures. Characterization of spin transfer torque and magnetization manipulation in magnetic nanostructures chen wang, ph. In order to do this, an original experimental setup was developed which allows to.
Spin injection and detection in magnetic nanostructures. Inoue department of applied physics, nagoya unirersity. The aim of this thesis work was to obtain a deeper understanding of spin dependent transport by the study of mixed effects of heat and charge currents in magnetic nanostructures. For the stt effect, a spinpolarized electric current is used to alter the magnetic state of a ferromagnet. Spin transport in magnetic nanostructures, the american journal of physics on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. The nanostructures might be favorable candidates for ferromagnetic contacts in future spininjection experiments. Spin transport in magnetic nanostructures listed as stmn. This increases the effect of spin dependent scattering on the electrons passing through the. Spindependent transport in antiferro and ferrimagnetic. Theory of spindependent tunneling and transport in magnetic nanostructures invited.
Timedomain measurements address the question of how fast a. Firstprinciples study on the electronic structure and transport property of the boron nitride sheet bnc structure, in which a triangular graphene flake surrounded by a hexagonal boron nitride sheet, is implemented. In this sense, the spin charge separation of electrons is a starting point for the physics of spinelectronics. Spindependent quantum interference within a single magnetic. Spin dynamics and spin transport jurgen lindner, daniel e. An efficient algorithm is developed to solve the scattering problem numerically. Recent theoretical studies predicted that local spin polarization on nonmagnetic surfaces as well as on magnetic nanostructures can be. Spindependent transport in nanostructures candidato dr. Spin transport and current induced magnetization dynamics. The study presented in this thesis is concerned with the spin dependent transport and spin transfer in magnetic nanostructures. Request pdf spin dependent transport in antiferro and ferrimagnetic nanostructures spin transfer torque stt and tunnelling magnetoresistance tmr in magnetic tunnel junctions with. Spin tunnel junctions have two magnetic electrodes separated by an insulating tunnel barrier made from aluminium oxide 36.
These structures include ferromagnetic f antiferromagnetic afnormal metal n nanostructures based on both conductive and insulating magneticsand heavy normal metals e. In magnetic systems of nanometer size, the interplay between spin and charge of electrons provides unique transport phenomena. We study the spin dependent transport properties of the nanostructures consisting of realistic magnetic barriers produced by the deposition of ferromagnetic stripes on heterostructures. Spin dependent transport in magnetic nanostructures crc press book in magnetic systems of nanometer size, the interplay between spin and charge of electrons provides unique transport phenomena. Nanosciences and nanotechnologies magnetism of nanostructures k. Spin transport in magnetic nanostructures hathaway, kristl. Spindependent transport in magnetic nanostructures is based on the physics of the interaction between spin and charge. This method eliminates the dominating resistivity component of the magnetic response and thus reveals an intrinsic spindependent process. Spin transport in magnetic tunnel junctions quantumatk q. Coherent electronic transport through a molecular device is studied using nonequilibrium greens function negf formalism. The plane magnetic nanostructures for the study of the spin transfer effect frank joseph albert, ph. This book introduces and explains the basic physics and applications of a variety of spin dependent transport phenomena in magnetic nanostructures with particular emphasis on magnetic multilayers and. Abstract a quasi onedimensional model of spin transport in heterogeneous.
The spinpeltier effect describes spindependent heat transport across this interface. The molecule itself is described with the help of hubbard model coulomb interactions are treated by means of the hartreefock approximation, while the coupling to the. Spintransport and transfer in magnetic nanostructures. Radiation effects on the magnetism and the spin dependent. Perpendicular transport of spinpolarized electrons through. In this chapter is developer a formalism to study quantum networks of generic shape in presence of rashba effect and magnetic field. This enables us to discuss recent controversy on spin injection and detection experiments. Manufacture, physics, devices, and modeling, march 9, 2008 department of physics, new york university andrew d.
Moreover, by introducing x vacancy into crx3gr, an ohmic contact forms in spin up direction. Quantum transport in noncollinear magnetic nanostructures. In magnetic superlattices, magnetic and nonmagnetic metallic thin films with thickness of the order of one nanometer are piledup alternately. 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 gra. Shinjo spin dependent transport in magnetic nanostructures.
Spin transfer torques in high anisotropy magnetic nanostructures eric fullerton1, jordan katine2, stephane mangin3. The charging energy of a metallic grain called a dot embedded in a nanowire causes the single electron tunneling. We employ landauers formalism to study spin dependent electron transport in structures like spin valve, magnetic tunnel junction and nanowires. It is shown that, only in the nanostructures with symmetric magnetic field with respect to the magneticmodulation direction, electrons exhibit a considerable. Request pdf spindependent transport in antiferro and ferrimagnetic nanostructures spin transfer torque stt and tunnelling magnetoresistance tmr in magnetic tunnel junctions with. Spin transport and current induced magnetization dynamics in magnetic nanostructures. In magnetic superlattices, magnetic and non magnetic metallic thin films with thickness of the order of one nanometer are piledup alternately. Spin dependent thermoelectric effects in magnetic nanostructures. We derive a general expression for the spin accumulation signal which covers from the metallic to the tunneling regime. A second driver for the growth of the study of spin transfer effects is that experimental fabrication techniques have only recently been developed that allow devices to be readily made at the sub 100 nm dimensions. Cornell university 2012 this dissertation describes a number of research projects with the common. We observed spindependent quantum interference by means of spinpolarized stm spstm 6, a technique sensitive to surface magnetization. The first two chapters are dedicated to introduce spin electronics, electrical transport and the experimental techniques commonly used in this work.
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