About the Book
The book proposes to cover comprehensively all aspects to understand the physics, design, characterization, simulation, and potentially implementation of 3D nanomagnetic and spintronic objects for applications.
Key Features
Provides an overview of an emerging field, for which there is no other comprehensive overview existing.
Combines academic knowledge, practical techniques for the implementation, and applied reviews
Brings together several experts from complementary fields, in each chapter, to avoid the juxtaposition of independent and scattered contributions.
Addresses concerns of low-carbon ICT and sustainability, making use of the prospects for low energy consumption of spintronics, and miniaturized nanodevices to achieve various clever functions, e.g. in IoT.
Table of Contents:
1. Magnetostatics in 3D – O. Fruchart (SPINTEC Grenoble), Anthony Arrott (emeritus, or
André Thiaville, LPS Paris)
o Basics of magnetostatics
▪ Basics: Maxwell and the various ways to handle
▪ Demag coefficients and their generality & validity
▪ Length scales
o Role in determining/ stabilising 3D textures:
▪ Importance of magneto-statics, facing in practice challenges in
simulation/modeling to take them into account
▪ Single-domain, near-single-domains, flux closure patterns described in general
terms.
▪ Magnetostatics versus chirality
o Range of dipolar fields
▪ Concepts, misconceptions, examples, dipoles and multipoles
▪ Coding information in 3D
2. Spin textures & topological textures in 3D – Claire Donnelly (MPI Dresden), Paul Sutcliff
(Durham University), Attila Kakay (HZDR Dresden)
o Accessible introduction to 3D textures, topology, chirality, curvature.
o 3D spin textures in the bulk
▪ 2D→ 3D structure in the bulk, skyrmions and skyrmions tubes & transformations
▪ Hopfions: what are they, predictions
▪ Magnetic vortex rings, vortices in 3D
▪ Bloch points.
▪ Bring together concepts and experimental realisations, lightly describe assets for
functions and applications
o 3D spin textures in confined geometries
▪ Flux-closure patterns in compact objects
▪ Wires (micro and nano) and rods
▪ Shells: spheres, tubes, core-shell
▪ 3D architectures and superlattices, 3D frustrated systems
o Spintronics and dynamics of spin textures ▪ DW dynamics
▪ Spin waves
▪ Magnonic crystals
Methodologies
NB: writing driven by objectives for achievements, capacities of each technique to address
them, frontiers and prospects
3. Synthesis, focusing on functions of the resulting materials – Amalio Fernandez Pacheco
(Zaragoza), Rui Xu (HZDR Dresden), Bethanie Stadler (Univ. Minnesota, USA), Oliver
Gutfleisch (TU Darmstadt) or Dieter Suess (Univ Vienna)
o Broad overview of synthesis routes (non-exhaustive list below)
▪ Top-down
• 3D direct nanoprinting: FEBID
• Additive manufacturing @micrometer/mm length scales (see also dedicated
chapter)
▪ Scaffolds + synthesis
• Templates: 2-photon litho, anodized alumina, polycarbonate foils and their
engineering
• Capping / filling techniques: electroplating, ALD, electroless…
▪ Self-construction :origami, rolling etc.
o Discussion should be driven by the properties sought or obtained, of importance for
magnetic and spintronic materials: magnetization, exchange, symmetry,
microstructure, roughness, resistivity, magnetic damping etc.
4. 3D magnetic characterization – Daniel Wolf or Axel Lubk (IFW Dresden), Claire Donnelly
(MPI Dresden), Charudatta M. Phatak (Argonne, USA), Olivier Fruchart (SPINTEC
Grenoble), Ingo Manke.
o Driven by questions and capacities to answer them, not an exhaustive review of all
techniques. Criteria: what is probed, sensitivity, spatial resolution, combine structure
and magnetism, elemental sensitivity, time resolution, 2D/3D.
o Yet, mention those:
▪ Pseudo-2D: XMCD projections (shadow-PEEM, (S)TXM), lens-less including
ptychography, electron holography, neutron bulk imaging, scanning near-field
microscopies (NV center, Magnetic force microscopy, Hall probe etc.).
▪ 3D imaging and reconstruction: methodology (lamino, tomo…), techniques,
reconstruction algorithms, limitations/ challenges.
o Entanglement of microscopy/topography and numerical simulations
o What can be observed/ probed, rather than how?
o Combine with how to interpret, and pitfalls to watch out for? E.g. XMCD tomo: limit
on imaging divergent structures.
5. Numerical micromagnetics – Richard Evans(Univ York), Dieter Suess(Univ Vienna), Attila
Kakay (HZDR Dresden), Daria Gusakova (SPINTEC Grenoble), V. Lomakin (San Diego)
o Basics of the micromagnetics theory
o Numerical implementations. Discuss efficiency and reliability.
o Multiscale, atomistic, LLB etc.
o Display, analysis and topological understanding of 3D magnetization textures (for the
physicists). Examples: visualization toolkit (surface and open views, cuts and
unrolling, iso lines and surface, color maps with artefacts for the human eye…),
processing (calculation of topological numbers, vorticity, charges etc.).
o Display, analysis and topological understanding (for the physicists)
o Entanglement of microscopy/tomography and numerical simulations: numerical
triples (rather than twins): make the most of advanced instruments to extract most
information from experimental data; make the most of simulations to compare with
reality.
eBook Project Approval Meeting title information sheet v3.5
Functions and applications
NB: writing driven by functions, potential use, challenges and work ahead
6. Magnetic storage and computing in 3D – L. Prejbeanu, K. Garello (SPINTEC, Grenoble),
Hideo Ohno or Kyota Watanabe (Tohoku)
o Short review of 2D technologies, highlight limitations
o 3D stacks, torques and spin textures
o PSA-MRAM, 3-terminal SOT-MRAM (?). Address: “3D Racetrack, where are we?”
Technological details on how realistic it is, e.g. current densities…
o 3D architectures for artificial intelligence (??)
7. 3D MEMS, magnetic sensors, actuators and other devices –Johannes Paul (Sensitech
GmbH, backup Claire Baraduc SPINTEC Grenoble), Orphé Cugat (G2Elab – Grenoble),
Johan Paulides (Advanced electromagnetics, The Netherlands)
o Sensing 3D magnetic fields
o Magnetic MEMS and NEMS (incl. FEBID actuators, see Paolo Vavassori)
o 3D magnetic architectures for production of 3D magnetic fields, energy production/
harvesting/ magnetocalorics
8. 3D magnetic nanorobotics – Bradley Nelson (ETH Zürich), Jizhai Cui (Univ. Fudan, China),
Robert Streubel (Univ. Nebraska)
o Swimmers – Bradley Nelson
o 3D “Origami”, bio and reconfigurable devices – Jizhai Cui
o Magnetic fluids etc. – Robert Streubel, T Russell https://www.mdpi.com/1996-
1944/13/12/2712
