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Magnons are excitations of magnetic materials that can have topological properties similar to those of electrons. Here, the authors show that the magnons of the bulk ferromagnet Mn₅Ge₃ are topological and can be controlled with a magnetic field.

Dzyaloshinskii–Moriya interaction (DMI) is one of the key factors to control the chiral spin textures in spintronic applications. Here the authors demonstrate the correlation of the DMI with the anisotropy of the orbital magnetic moment and magnetic dipole moment in Pt/Co/MgO ultrathin trilayers.

Authors investigate graphene/cobalt and graphene/nickel interfaces, and observe a non-zero Dzyaloshinskii–Moriya interaction that they attribute to the Rashba effect; calculations suggest the effect can be enhanced in van der Waals heterostructures.

The Dzyaloshinskii–Moriya exchange induces a range of chiral phenomena in spintronic systems. Experiments now confirm that this interaction is proportional to the Heisenberg exchange, reflecting their common origins despite their opposite symmetries.

Single crystals of a two-dimensional quantum spin system with geometric frustration lead to the observation of a ‘pinwheel’ valence-bond ground state. In this case, the distortion of the ideal kagome lattice structure helps to stabilize the quantum spin state.

The emergent electric field induced by pinned magnetic solitons remains poorly understood. Now the dissipative motion of magnetic domain walls under an alternating current in Weyl magnet NdAlSi devices is shown to induce a large emergent electric field.

Focused ion beam-based nanofabrication enables the production of 3D helical devices from single-crystalline Co₃Sn₂S₂. The resulting chiral geometry-driven symmetry breaking produces a diode-like electrical response in transport measurements.

Small-angle neutron scattering experiments of the layered antiferromagnet Ca₃Ru₂O₇ reveal a metamagnetic spin texture that is indicative of an extraordinary coexistence of spin orders belonging to different symmetries.

Information technology based on few atom magnets requires both long spin-energy relaxation times and flexible inter-bit coupling. Here, the authors show routes to manipulate information in three-atom clusters strongly coupled to substrate electrons by exploiting Dzyaloshinskii–Moriya interactions.

Current-driven domain wall propagation in ferromagnetic layers adjacent to normal metals can be very fast, which could recently be explained by their chirality. Here, the authors show means of controlling the magnetic chirality, which opens the possibility to tune the dynamics of domain walls.

The coupling of ferroelectric and antiferromagnetic order in BiFeO₃ makes it appealing for applications however the presence of domain structure acts to undermine this potential. Here, the authors demonstrate BiFeO₃thin films with a single domain of electrical polarization and canted antiferromagnetic order.

Skyrmions are stable topological textures with particle-like properties — a mathematical concept that was originally used to describe nuclear particles but has since turned up at all scales. Last year, the presence of skyrmions in the magnetic compounds MnSi and Fe_1−xCo_xSi was confirmed with neutron-scattering experiments. Here, real-space images are presented of a two-dimensional skyrmion lattice in a thin film of the latter compound. The observed nanometre-scale spin topology might reveal new magneto-transport effects.

Magnetic domain walls can exhibit a variety of different spin textures. Chen et al. show that it is possible to switch these textures between left handed, right handed, cycloidal, helical and mixed domain wall structures by controlling uniaxial strain in iron/nickel bilayer thin films on tungsten.

Sr₃Ru₂O₇ exhibits a quantum critical point tunable by magnetic field and has been widely used in the study of criticality. Here, by using inelastic neutron scattering, the authors measure collective magnetic excitations near the quantum critical point and relate them to thermodynamic properties and spin density wave order.

Multiferroics are promising for their simultaneous ferroelectricity and magnetism, although in some of the most promising compounds the ferroelectric polarization remains small. Here, the authors show that applying external pressure to the multiferroic TbMnO₃leads to a high ferroelectric polarization.

Cupric oxide is a multiferroic that shows a magnetically induced electrical polarization. Here, the authors discover that in this compound an electromagnon, a mixed spin-lattice excitation, occurs at substantially higher temperatures than in related materials.

The hunt for a quantum spin liquid has involved many different material families and models. Now, Zn-barlowite has been found to have similar behaviour to another candidate material, herbertsmithite, hinting there may be universal physical behaviour.

Experimental realizations of magnetic skyrmions, particle-like spin swirls with topological protection, so far have required inversion symmetry breaking or a geometrically frustrated lattice. In centrosymmetric GdRu₂Si₂, in which a geometrically frustrated lattice is absent, a skyrmion lattice phase emerges, which is probably stabilized by four-spin interactions mediated by itinerant electrons in the presence of easy-axis anisotropy.

SrCu2(BO3)2 is a 2D quantum antiferromagnet on a particular frustrated lattice showing multiple magnetization plateaus and quantum phase transitions under high pressure. Here the authors uncover novel magnetic phases in this material under combined effects of extreme magnetic field and pressure.

In many quantum magnets, an applied magnetic field competes with the expected zero-field state, leading to complex magnetic behavior. Okuma et al. observe the formation of quantum magnetization plateaus in a kagomé antiferromagnet and argue they form due to the crystallization of magnon excitations.

BiFeO₃is one of the most widely studied multiferroic materials, as it offers a strong coupling between magnetism and electric polarization up to room temperature. Here, studying monodomain crystals, the authors find an additional electric polarization component orthogonal to the widely studied one.

Neel domain walls are typically stabilized by an interfacial Dzyaloshinskii-Moriya interaction, with a chirality that is fixed by the sample materials. Here, Song, Huang and coauthors demonstrate the existence of two bistable Néel domain wall states with opposite chiralities, and the switching between these via magnetic field pulses

Magnetic interactions in solids are usually short-range or else they involve itinerant electrons. Here, the authors evidence a long-range magnetic coupling mediated by orbital moments in a polar spacer layer of nonmagnetic insulating oxide, with a sign which oscillates with spacer thickness.

The resonant microwave excitation response of metals, semiconductors and insulating chiral magnets is studied by examining their entire magnetic phase diagrams, which includes the skyrmion lattice phase. A unified model to explain this response is also developed.

The ability to control domain wall motion in ultrathin magnetic wires with an applied current could prove useful in future spintronic devices. Tetienne et al.now directly observe the different domain-wall structures in various magnetic material systems using a scanning nanomagnetometer.

Fe₃GeTe₂, known as FGT, is a van der Waals magnetic material that was recently shown to host magnetic skyrmions. Here, Birch et al using both X-ray and electron microscopy to study the stability of skyrmions in FGT, revealing how the sample history can influence skyrmion formation

Spin waves are excited in a thin film of bismuth-doped yttrium iron garnet using radio-frequency pulses and interact with magnetic domain walls. Pulses as short as 1 ns translate a domain wall over 15 µm distances, offering control over domain-wall dynamics.

Antiferromagnets exhibit high frequency magnons, in the THz regime, a point potentially useful for applications, however, it has meant that detecting spin-fluctuations in antiferromagnets is typically too fast for current experimental approaches. Here Weiss et al use femtosecond noise correlation spectroscopy to observe magnon fluctuations in Sm0.7Er0.3FeO3.

Magnetic skyrmions are particle-like magnetization textures which may be manipulated in thin-film device applications. Here, the authors demonstrate the formation and control of room-temperature artificial skyrmion lattices in Co/Pd multilayers, defined by local ion irradiation and an array of magnetic vortex discs.

In a magnetoelectric material, an applied electric field can drive changes in the magnetic order. This feature has profound technology prospects and here, Moody et al demonstrate deterministic control of the direction of magnetic spiral order via an applied electric field in Cu₂OSeO₃.

The energy efficient control of magnetisation for memory applications is one of the most important challenges in the field of spintronics. The authors investigate theoretically the possibility of the switching a one-dimensional antiferromagnet using an external electric field.

Uniaxial strain as small as 0.3% in FeGe thin films can induce large anisotropic deformation of magnetic skyrmions and their crystal lattice hosted in the material.

Thermoelectric effects are limited to electrons to occur, and disappear at low temperatures due to electronic entropy quenching. Here, the authors report thermoelectric generation caused by nuclear spins down to 100 mK due to nuclear-spin excitation in a magnetically ordered material MnCO₃.

Theoretical studies of quantum magnetism typically assume idealised lattices with freely tunable parameters, which are difficult to realise experimentally. Zvyagin et al. perform challenging measurements at high pressures to tune and to accurately monitor the exchange parameters of a triangular lattice antiferromagnet.

A detailed experimental investigation on the spin excitations in SrCu₂(BO₃)₂ under an external magnetic confirms the existence of topological triplon modes in this experimental realization of the Shastry–Sutherland model.

Spin current is generated by pumping from nuclear spin waves. The nuclear magnetic resonance is used to transfer angular momentum from the nuclei of an antiferromagnet to a propagating spin current that is subsequently collected in a distant electrode.

Topological magnetic spin structures such as skyrmions and merons have the potential to be used in magnetic information devices. Now multistep transformations between such structures are demonstrated in a centrosymmetric material.

Micromagnetic simulations describe both the current-induced motion of skyrmions in nanostripes and the nucleation of single skyrmions by spin-polarized currents.

We demonstrate the emergence of magnetism induced by a terahertz electric field in SrTiO₃.

The magnetism-induced chirality in electron transportation is of fundamental importantance in condensed matter physics but the origin is still unclear. Here the authors demonstrate that the asymmetric electron scattering by chiral spin fluctuations can be the key to the electrical magnetochiral effect in MnSi.

Wafer-scale realization of a nanoscale magnetic tunnel junction hosting a single, ambient skyrmion enables its large readout, efficient switching, and compatibility with lateral manipulation, and thereby provides the backbone for all-electrical skyrmionic device architectures.

Manipulating topological spin textures are demanded for future spintronic devices, but knowledge about phase transitions among different spin textures remain limited. Here, Fujishiro and Kanazawa et al. report chemical-pressure-controlled phase transitions between different topological spin textures in chiral magnets MnSi_1−xGe_x.

In the non-collinear antiferromagnet Mn₃Sn, a spin–orbit torque makes the collective octupole moment and individual moments rotate in opposite directions, leading to a sign-reversed switching polarity compared with collinear magnets.