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The creation of stable and isolated magnetic hopfions—three-dimensional topological solitons—has remained experimentally challenging. Now the laser-induced nucleation of hopfions has been achieved in a chiral magnet.

Skyrmions are magnetic solitons characterised by an integer topological charge. Here, the authors explore the formation of linked skyrmions, a configuration where multiple skyrmions are linked together with topological point defects, realised in a shifted magnetic bilayer where Dzyaloshinskii-Moriya interactions in each layer are orthogonal to each other.

Skyrmions are topologically protected field configurations that appear as solutions of continuous quantum-field theories. Recently, they have been observed in magnetic bulk alloys, where a lattice of skyrmions is stabilized by an external magnetic field. In contrast, this study finds evidence for a skyrmion lattice as a spontaneous ground state, encoded into a magnetic spin texture on the atomic scale.

In the Kondo effect, a bath of conduction electrons screens a localized magnetic moment. Here, the authors demonstrate Kondo screening of a normally isolated 4f-like moment in a magnetic molecule on a Cu(001) surface that is modulated by strong ligand-mediated coupling.

If single molecules are to be used in spintronic devices, it is necessary to interlink molecular spin states and charge transport. Here, the authors approach this goal by directly accessing highly spin-polarized hybrid states of a molecular complex of an early lanthanide on a metal surface.

To determine the topological character of a magnetic structure, one has to rely on techniques based on spin magnetism. Here, the authors study chirality-driven orbital moment physics and propose a new experimental protocol for the identification of topological magnetic structure, based on soft X-ray spectroscopy.

Friedel oscillations are ripples in the electron density surrounding a charge impurity. Bouhassoune et al. now use first-principle calculations to show that Friedel oscillation surrounding an oxygen impurity in a ferromagnetic film can be engineered and amplified by choice of substrate and film thickness

Manganese oxide self-organizes on Ir(100) surfaces to form arrays of one-dimensional chains, providing a model system to study emergent magnetic behaviour. Schmitt et al. demonstrate they host chiral magnetism mediated by Dzyaloshinskii–Moriya-enhanced RKKY interactions.

Clear understanding of the influence from material inhomogeneities and defects is one of the keys to achieve reliable Skyrmion based devices. Here the authors report their first principles studies on the interaction of single skyrmions with single-atom impurities and reveal its universal shape originated from the defect’s electron filling.

Small clusters of magnetic atoms can behave in very different ways to those same atoms in bulk. Arranging iron atoms one by one into complex but well-defined patterns on a copper surface enables the construction of nanoscale magnetic structures with tailored characteristics.

Spin–orbit torques in heavy metal/ferromagnetic layers have a complex dependence on the magnetization direction. This dependence can be exploited to increase the efficiency of spin–orbit torques.

Skyrmions—magnetic vortices that can behave like particles—have recently been observed in ultra-thin transition metal films. Dupé et al. show how the structure and composition of the interface influence the size and stability of the skyrmions.

When molecules of a phenalenyl derivative, which has no net spin, are deposited on a ferromagnet, they develop into a magnetic supramolecular layer with spin-filtering properties; this could be the basis for a new approach to building molecular magnetic devices.

The Ruderman–Kittel–Kasuya–Yosida interaction indirectly couples the moments of magnetic atoms through conduction electrons. Using a spin-polarized scanning tunnelling microscope, the direction and strength of this interaction between pairs and triplets of isolated atoms on a surface has been imaged directly.

Magnetic skyrmions are particle-like configurations which can emerge in the magnetization of materials possessing a chiral exchange interaction. Here, the authors demonstrate how spin-mixing magnetoresistance can allow for the reliable perpendicular detection of single nanoscale skyrmions in Pd/Fe/Ir(111) thin films.

Transmission electron microscopy is used to observe three-dimensional topological solitons known as hopfions that in a chiral magnet are found to form rings around skyrmion strings, and a nucleation protocol for these rings is provided.

Topological insulators possess dispersionless electronic surface states with perpendicular spin-momentum locking which may be utilised in spintronic devices. Here, the authors demonstrate p–n junctions formed from two topological insulator thin films, tuning the junction type by film thickness.

Coexistence of a topological insulator phase and a topological crystalline insulator phase helps to maintain topological properties under a controlled symmetry breaking perturbation. Here, Eschbacket al. report a superlattice of Bi and Bi₂Te₃to be such a dual topological insulator.

Proposals for skyrmion-based high-density memory devices require an understanding of the formation and shape of skyrmions in confined geometries. Here, the authors use electron holography to image magnetic textures in FeGe nanostripes and explore the parameters governing skyrmion morphology.

An intrinsic antiferromagnetic skyrmion is located entirely within a single atomic layer, rather than two coupled layers. Here, the authors predict the existence of intrinsic antiferromagnetic skyrmions in a chromium monolayer deposited on a PdFe/Ir(111) substrate, which can form interlinked chain structures.

It has been predicted that elemental Iron, with low dimensionality, will be a topological metal hosting Weyl nodes. Here, Chen et al. grow iron on tungsten, a heavy metal with a strong spin-orbit interaction, and using momentum microscopy, show the emergence of giant open Fermi arcs which can be shaped by varying the magnetization of the iron.

One challenge for encoding information in chiral spin textures is how to read the information electrically. Here, Lima Fernandes et al. show that chiral spin textures exhibit a magnetoresistance signature which could allow for efficient electric readout of the chirality and helicity.

Skyrmions are topological two-dimensional spin textures that in three-dimensional systems resemble strings or tubes. Here, using transmission electron microscopy Zheng et al observe the braiding of skyrmion strings in FeGe and predict this phenomenon for a large family of magnets.

Recent advances in classifying magnets according to spin-group symmetry have expanded the possibilities of unconventional magnetism. Unconventional magnets — such as collinear spin-split antiferromagnets, also known as altermagnets, noncollinear spin-split antiferromagnets and anomalous-Hall antiferromagnets — combine the advantages of ferromagnetism and antiferromagnetism.

Magneto-optical effects in magnets are commonly attributed to the interplay between exchange splitting and spin-orbit coupling. Here, Feng et al. report a topological magneto-optical effect in non-coplanar antiferromagnets due to finite scalar spin chirality, without any reference to exchange splitting or spin-orbit coupling.

Whether topological semimetal states can emerge in two-dimensional magnetic materials remains less understood. Here, Niu and Hanke et al. propose the concepts of mixed Weyl and nodal-line semimetallic phases by including the magnetization direction into the topological analysis in two-dimensional ferromagnets.

Carbon nanosystems on an iron monolayer create organic–metal hybrids with tunable magnetic properties that can be magnetically coupled to each other over nanometre distances.

Electric-field control of magnetization switching is highly promising for low-dissipation spintronics. Here, the authors propose an electrically induced topological phase transition mediated by spin orbit torques as attractive way to control magnetization in absence of longitudinal charge currents.

Skyrmions, localized defects in the magnetization, can be stabilised in materials by the Dzyaloshinskii-Moriya interaction (DMI). Hoffmann et al. predict that, when the DMI is anisotropic, antiskyrmions can be formed and coexist with skyrmions, enabling studies and exploitation of their interactions.

Magnetic skyrmionic bubbles have been reported for Fe₅GeTe₂ and other layered van der Waals materials and are good candidates for applications in spintronics. Here, the authors report a near room temperature skyrmionic structure for Fe₅GeTe₂ and study the magnetic ordering for pre and post-cooling states using a combination of magnetic measurements and DFT calculations.

Magnetic skyrmions—a type of localized spin texture—have been theoretically predicted to annihilate with counterparts known as antiskyrmions. By means of electron microscopy, such annihilation has now been observed in a cubic chiral magnet.

In principle skyrmions are topologically protected, but the crystal lattice interferes with this protection so that they should be unstable to switching of their winding number. Here this process is understood via scanning tunnelling microscopy.

Electron holography enables direct experimental verification of the existence of chiral bobbers in thin films of chiral magnets.

Verification efforts of density-functional theory (DFT) calculations are of crucial importance to evaluate the reliability of simulation results. In this Expert Recommendation, we suggest metrics for DFT verification, illustrating them with an all-electron reference dataset of 960 equations of state covering the whole periodic table (hydrogen to curium) and discuss the importance of improving pseudopotential codes.

Band degeneracies at the Fermi level in topological semimetals are sources of intriguing interference effects between electronic states around the degeneracy points. Here, the RE₈CoX₃ compounds, with RE = rare-earth and X = Al, Ga, or In, are proposed as realizations of ideal spinless Dirac semimetals hosting the fourfold degenerate band-crossing points without the spin degrees of freedom.

The Hall effect is about the generation of a transverse voltage when a longitudinal current is applied and many mechanisms can lead to Hall effect in magnetic material. Here, the authors report a chiral Hall effect that is proportional to the vector spin chirality in canted magnetic materials.

Control of spin textures and stabilisation of chiral magnetic states is typically approached using external electrical and magnetic fields but optical manipulation offers another exciting avenue to explore. Here, the authors theoretically investigate the underlying physics of laser-driven chiral magnetism highlighting the connection between the quantum evolution of electronic states and the classical spin dynamics.

Spintronic devices, where the spin of the electron becomes the main carrier of information, offer a promising avenue to develop quantum devices. The authors experimentally and theoretically investigate spin-polarization and spin-orbit mixing in a W(110) surface, and provide a mean to fine tune the quantum (de)coherence of materials by changing the spin polarization of a conduction electron in a spintronic device