Multilayer Magnetic Nanostructures: Properties and Applications

Introduction
Contents
About the Author
Abbreviations
1 Physical Foundations for the Formation of Magnetic Nanostructures
	1.1 The Phenomenon of Giant Magnetoresistance
	1.2 GMR Theory
	1.3 Tunnel Magnetoresistance
	1.4 Spin-Polarized Current
	1.5 MRAM (Magnetoresistive Random Access Memory)
	1.6 Superparamagnetic Limit
	References
2 Frustrations of Exchange Interaction
	2.1 Why Does Spin Feel Hopeless?
	2.2 Frustrations in a System with a Non-magnetic Layer
	2.3 Frustrations in the Ferromagnet–Antiferromagnet System
		2.3.1 Uncompensated Cross-Section of the Antiferromagnet Surface
		2.3.2 Compensated Cross-Section of the Antiferromagnet Surface
	References
3 Domain Walls and the Phase Diagram of the Spin-Valve Systems with a Non-magnetic Layer
	3.1 Domain Wall Generated by Frustration
	3.2 Phase Diagram
	3.3 Behavior in a Magnetic Field
	3.4 Experimental Observations
	References
4 A Thin Film of a Ferromagnet on an Antiferromagnetic Substrate: Uncompensated Slice
	4.1 Model Description
	4.2 Solitary Domain Wall
		4.2.1  γaf >>1
		4.2.2  γaf <<1
	4.3 Spin Vortices
	4.4 Phase Diagram
	4.5 Experimental Results
	References
5 Compensated Slice
	5.1 Spin-flop Orientation
	5.2 The Case of “Charged” Edges of Atomic Steps at the Interface “Ferromagnet–Antiferromagnet”
		5.2.1 Case of Weak Roughness
		5.2.2 A Case of  Strong Roughness. Thick Layer
		5.2.3 A Case of  Strong Roughness. Thin Layer
	References
6 Behavior in a Magnetic Field
	6.1 Exchange Bias. Uncompensated Slice
	6.2 Exchange Bias. Compensated Slice
	6.3 A Substrate of Finite Thickness. “Switching” the Nanodomain State
		6.3.1 The Area of Strong Fields
		6.3.2 The Area of  Medium Fields
		6.3.3 Weak Field Area
		6.3.4 The “Switching” Field
		6.3.5 Going Beyond the Exchange Approximation
	6.4 Exchange Bias Near the Neel Temperature
	References
7 Spin-Valve Structure Ferromagnet–Antiferromagnet–Ferromagnet
	7.1 Frustrations in a Three-Layer System
	7.2 Domain Walls in a Three-Layer System
		7.2.1  γf, af a/γaf ll1
		7.2.2  γf, af a/γaf gg1
	7.3 Phase Diagram
	7.4 Phase Transition “Polydomain State—Monodomain State with Exchange Spirals” in the Antiferromagnetic Layer
		7.4.1 Simulation Results
		7.4.2 Analytical Model
	7.5 Behavior of a Spin-Valve Structure in a Magnetic Field in the Region of Applicability of the Exchange Approximation
	7.6 Comparison with the Experiment. Magnetic Phase Diagram of a Spin-Valve Structure with an Antiferromagnetic Oxide Layer
		7.6.1 Phase Diagram
		7.6.2 Comparison with the Experiment
	References
8 Surface Spin-flop Transition in Antiferromagnet
	8.1 Volume Spin-flop Transition
	8.2 The Case of an Atomically Smooth Surface
	8.3 Size Effects in a Plane-parallel Layer of an Antiferromagnet with Smooth Surfaces
		8.3.1 Even Number of Atomic Planes
		8.3.2  Odd Number of Atomic Planes
	8.4 Semi-infinite Antiferromagnet with Uncompensated Rough Surface
	8.5 Antiferromagnet Layer with an Uncompensated Rough Surfaces
		8.5.1 Thin Layer
		8.5.2 Thick Layer
	8.6 Possibilities of Experimental Observation
	References
Conclusion