scholarly journals Обменные взаимодействия в гетероструктурах NiFe/Ta/IrMn в условиях дефицита Ta

2020 ◽  
Vol 62 (6) ◽  
pp. 915
Author(s):  
Р.Б. Моргунов ◽  
А.Д. Таланцев ◽  
М.В. Бахметьев ◽  
Н.В. Грановский
Keyword(s):  
Exchange Bias ◽  
Exchange Interactions ◽  
Contact Exchange ◽  
Conduction Electrons ◽  
Ferromagnetic Layers ◽  
Temperature Dependences ◽  
Interlayer Exchange ◽  
First Contact

In the NiFe/Ta/IrMn structures, the contributions of two types of exchange interactions are separated at the NiFe/IrMn interface, partially separated by non-magnetic Ta fragments. The first “contact” exchange corresponds to the NiFe/IrMn fragments. The second “interlayer” exchange is provided by the Ta conduction electrons in the NiFe/Ta/IrMn fragments. A comparison of the temperature dependences of the exchange bias in heterostructures with varied Ta spacer at fixed parameters of the ferromagnetic layers allowed us to separate the contributions of the above types of exchange interactions and to establish their temperature dependences. The energies of the exchange interactions in the NiFe/IrMn and NiFe/Ta/IrMn fragments were determined.

Micromagnetic Analysis of Temperature Dependences of Hysteresis Properties of Polycrystalline Films with Exchange Bias

2021 ◽  
Vol 122 (9) ◽  
pp. 855-860
Author(s):  
N. A. Kulesh ◽  
M. E. Moskalev ◽  
V. O. Vas’kovskii ◽  
E. A. Stepanova ◽  
V. N. Lepalovskii
Keyword(s):  
Exchange Bias ◽  
Polycrystalline Films ◽  
Temperature Dependences ◽  
Hysteresis Properties

scholarly journals Control of the noncollinear interlayer exchange coupling

2020 ◽  
Vol 6 (48) ◽  
pp. eabd8861
Author(s):  
Zachary R. Nunn ◽  
Claas Abert ◽  
Dieter Suess ◽  
Erol Girt
Keyword(s):  
Exchange Coupling ◽  
Magnetic Moments ◽  
Interlayer Exchange Coupling ◽  
Magnetic Structures ◽  
Spintronic Devices ◽  
Spacer Layer ◽  
Ferromagnetic Layers ◽  
Almost All ◽  
Interlayer Exchange ◽  
Coupling Angle

Interlayer exchange coupling in transition metal multilayers has been intensively studied for more than three decades and is incorporated into almost all spintronic devices. With the current spacer layers, only collinear magnetic alignment can be reliably achieved; however, controlling the coupling angle has the potential to markedly expand the use of interlayer exchange coupling. Here, we show that the coupling angle between the magnetic moments of two ferromagnetic layers can be precisely controlled by inserting a specially designed magnetic metallic spacer layer between them. The coupling angle is controlled solely by the composition of the spacer layer. Moreover, the biquadratic coupling strength, responsible for noncollinear alignment, is larger than that of current materials. These properties allow for the fabrication and study of not yet realized magnetic structures that have the potential to improve existing spintronic devices.

Exchange Coupling and Its Applications in Magnetic Data Storage

2007 ◽  
Vol 7 (1) ◽  
pp. 13-45 ◽  
Author(s):  
Kebin Li ◽  
Yihong Wu ◽  
Zaibing Guo ◽  
Yuankai Zheng ◽  
Guchang Han ◽  
...  
Keyword(s):  
Data Storage ◽  
Exchange Bias ◽  
Exchange Coupling ◽  
Quantum Confinement Effect ◽  
Hard Disk Drives ◽  
High Sensitivity ◽  
Theoretical Models ◽  
Magnetic Data ◽  
Interlayer Exchange Coupling ◽  
Interlayer Exchange

The continuing scaling of magnetic recording is facing more and more scientific and technological challenges because both the read sensor and recording bit are approaching sub-50 nm regime with the ever increasing areal density in hard disk drives. One of the key and indispensable elements for both high-sensitivity sensors and high-density media is the exchange bias between a ferromagnetic and an antiferromagnetic layer or the exchange coupling between two ferromagnets via a non-magnetic spacer. In the nanometer regime, the exchange coupling between ferromagnet and antiferromagnet or two ferromagnets through a conductive spacer is governed by the intergrain exchange interaction which has its origin in electron spins. Interlayer exchange coupling in multilayer or trilayer essentially originates from the quantum confinement effect. In this paper, we first review the physical origin and various theoretical models of the two types of exchange couplings, followed by a review of the applications of the exchange bias and interlayer exchange coupling in data storage with emphasis on the advanced read sensor and advanced media including perpendicular media and patterned media.

scholarly journals Критические свойства в модели Изинга на треугольной решетке с переменным межслойным обменным взаимодействием

2019 ◽  
Vol 61 (10) ◽  
pp. 1898
Author(s):  
А.К. Муртазаев ◽  
М.К. Рамазанов ◽  
М.К. Бадиев
Keyword(s):  
Order Parameter ◽  
Finite Size ◽  
Exchange Interactions ◽  
Universality Class ◽  
Correlation Radius ◽  
Ising Models ◽  
Finite Size Scaling ◽  
Antiferromagnetic Ising Model ◽  
Interlayer Exchange ◽  
Range Of Values

The Monte Carlo replica algorithm studies of phase transitions and critical phenomenaofthe layered triangular antiferromagnetic Ising model withvariable interlayer exchange interaction. Investigations were carried out for the ratios of the value of the intralayerJ1 and interlayer J2 exchange interactions in the range of values r = J2 / J1 = 0.01 ÷ 1.0. It was found that in the above range r is observed second-order phase transition.Static critical exponents for the heat capacityα, susceptibility γ, order parameter β, correlation radius ν, and the Fisher exponent ηare computed by means of the finite-size scaling theory. It is shown that the universality class of the critical behavior of the model is maintained in the range of 0.05 <r≤1.0.The results obtained suggest that3D frustrated Ising models on stacked triangularlattice with interlayer-to-intralayer exchange ratio 0.05<r≤1.0. preserves the universality class of criticalbehavior. At lower r, a crossover from 3D to 2D criticalbehavior is observed.

scholarly journals Термодинамические и магнитные свойства двумерной анизотропной модели Изинга с конкурирующими взаимодействиями

2019 ◽  
Vol 61 (10) ◽  
pp. 1911
Author(s):  
А.К. Муртазаев ◽  
Ж.Г. Ибаев
Keyword(s):  
Exchange Interactions ◽  
Square Lattice ◽  
Wave Number ◽  
Two Dimensional ◽  
Competing Interactions ◽  
Distinctive Features ◽  
Magnetic Parameters ◽  
Modulated Structures ◽  
Temperature Dependences ◽  
Competing Interaction

The two-dimensional anisotropic Ising model was studied with competing interactions on a square lattice using Monte-Carlo methods using the Wang-Landau algorithm. The temperature dependences of the main thermodynamic and magnetic parameters are calculated. The distinctive features of the temperature dependences of these parameters are shown for different values of the competing interaction. The graphs of the dependence of the wave number of modulated structures on the ratio of the parameters of exchange interactions are plotted. Built phase diagram of the model. Interpolating the phase boundaries of the diagram, the coordinates of the Lifshchits point and phase localization areas with different wave vector values are calculated.

Magnetism of a graphite bi-intercalation compound with two types of ferromagnetic layers: double hysteretic transition in CrCl3–NiCl2–C

1990 ◽  
Vol 68 (12) ◽  
pp. 1435-1439 ◽  
Author(s):  
D. G. Rancourt ◽  
S. Flandrois ◽  
P. Biensan ◽  
G. Lamarche
Keyword(s):  
Intercalation Compound ◽  
Exchange Interactions ◽  
Atomic Scale ◽  
Temperature Hysteresis ◽  
Low Field ◽  
Ferromagnetic Exchange ◽  
Graphite Intercalation ◽  
Ferromagnetic Layers ◽  
Double Transition ◽  
Plane Interaction

An atomic-scale multilayer with two types of ferromagnetic layers is achieved by graphite intercalation. It is a bi-intercalation compound with stacking sequence CrCl3NiCl2NiCl2/… where/represents a graphite layer. The two types of chloride layers are much as they occur in the pristine chlorides and have the same lattice parameters and intralayer intertransition–metal ferromagnetic exchange interactions. The transition temperatures for singly intercalated CrCl3 and NiCl2 graphite compounds are, respectively, 11.3, and 20.2 K. The bi-intercalation compound shows a "double transition" with Tc1 and Tc2 being equal to the relevant intercalate-specific temperatures. It is proposed that, as the temperature is lowered, the NiCl2 layers order first at Tc2 into a 3-D antiferromagnetic stacking of ferromagnetic planes, followed by onset of intra-CrCl3-layer ferromagnetic order at Tc1. Below Tc1 the two types of ferromagnetic planes probably assume a 3-D antiferromagnetic stacking that involve both types of layers, requiring that the NiCl2 stacking be different than at Tc1 < T < Tc2. The main interlayer interactions are believed to be dipole–dipole forces and these are seen to give large low-field temperature hysteresis effects. This is in contrast to many layered materials with antiferromagnetic in-plane interactions in which: (i) dipole–dipole forces do not play a significant role, (ii) 3-D order is not intercalate specific but occurs at temperatures that are much lower than the in-plane interaction strengths and that are highly dependent on the interlayer interaction strengths, and (iii) hysteresis effects are not observed.

Sign in / Sign up

Export Citation Format

Share Document