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Oscillations of the order parameter amplitude in magnetically ordered materials provide condensed matter analogues of the Higgs boson but in most cases they are unstable. Dally et al. show that the quasi-one-dimensional magnet α-Na_0.9MnO₂ supports stable amplitude excitations.

The isolation of graphene leads to a surge of interest in two dimensional materials, and recently, ferromagnetism has been observed in several two-dimensional materials. However, two-dimensional ferromagnetism remains rare. Here, Gong et al present an alternative approach to achieve two-dimensional ferromagnetism; combining antiferromagnetic FePS3 with non-magnetic WS2 they find a ferromagnetic state forms at the interface of these two materials.

Synchrotron Mössbauer source spectroscopy is used to reveal that haematite remains magnetic in cold subducting slabs at the depth of the transition zone in the Earth’s mantle, with implications for the locations of magnetic poles during inversions of the Earth’s magnetic field.

Electrons in uranium-based materials are often on the border between localised and itinerant behaviour, which can lead to unusual magnetic behaviour. Here the authors combine experiment and theory to show that USb₂ may be an unusually high temperature example of a singlet-ground-state magnet.

Some materials can display magnetic order despite having spin-singlet ground state on individual magnetic sites. This arises due to exchange interactions mixing excited crystal electric field states. Here, Gao et al study and example of such a system, Ni₂Mo₃O₈, and find that crystal electric field states in both the paramagnetic and antiferromagnetic states exhibit dispersive excitations.

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.

The exchange bias effect in IrMn/FeCo is driven by a phase transition in the IrMn layer at room temperature, and occurs without the typical field-cooling sequence across the antiferromagnet Neel temperature.

Using pump-power-dependent exciton absorption spectroscopy, the authors reveal magnon-mediated exciton–exciton interactions and a consequent nonlinear optical response in CrSBr, an antiferromagnetic semiconductor.

Sc₃In and ZrZn₂ are the only two known itinerant ferromagnets that form from non-magnetic constituents. Now, Svanidze et al.,evidence itinerant antiferromagnetism in TiAu below 36 K using thermodynamic, transport, muon-based and neutron-based measurements, and density functional analysis.

By examining the dynamics of skyrmions and antiskyrmions using a combination of atomistic spin simulations, reduced-variable modelling and machine learning algorithms, it is shown that current-induced spin–orbit torques can lead to trochoidal motion and skyrmion–antiskyrmion pair generation.

Traditionally quantum state tomography is used to characterize a quantum state, but it becomes exponentially hard with the system size. An alternative technique, matrix product state tomography, is shown to work well in practical situations.

A moiré potential may play a role in determining the magnetic properties of a two-dimensional homo or heterostructure. Now, non-collinear spin structures are observed in twisted double bilayer CrI₃, providing a platform to engineer unusual magnetic textures.

Current-induced magnetic domain wall motion can be triggered by an applied magnetic field, and its motion is described by the vector sum of the velocities imparted by current and magnetic field driving terms.

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.

Room-temperature electrical switching of a topological antiferromagnetic state in polycrystalline Mn₃Sn thin films is demonstrated using the same protocol as that used for conventional ferromagnetic metals.

Optical second harmonic generation technology quantitatively characterized the enhancement of antiferromagnetic order and Néel temperature in epitaxially strained BiFeO₃, providing a quantitative detection and manipulation for the antiferromagnetism.

Uranium dioxide fuels the world’s nuclear-power reactors, and so a full understanding of its thermal properties is essential. Gofryk et al. now demonstrate that, despite its cubic atomic structure, the thermal conductivity of uranium dioxide is anisotropic owing to phonon-spin scattering.

Devices based on antiferromagnetic materials have advantages of robustness to external magnetic fields and the potential for ultrafast operation. Here the authors present a multilevel antiferromagnetic memory cell that can be operated using standard electronic interfaces.

It has long been suggested that the inverse Fourier transform of neutron scattering data gives access to space- and time-resolved spin-spin correlations. Scheie et al. perform this procedure on high-precision experimental data from a 1D quantum antiferromagnet and uncover new features in short-term quench dynamics.

A method combining scanning transmission electron microscopy with high-resolution electron energy-loss spectroscopy enables the observation of magnons and their dispersion, and provides a way to examine magnetic inhomogeneities with nanometre spatial resolution.

2D dielectric materials with high dielectric constant (κ) are needed for the implementation of scalable electronic devices. Here, the authors predict 51 potentially exfoliable nonlayered oxide monolayers with high κ values, anomalous mechanical properties and large spin orbit coupling.

Although quantum phase transitions are attracting increasing attention as the conceptual link between conventional and exotic states of quantum matter—having been implicated, for example, in the properties of high-temperature superconductors—there are few model systems in which they can be studied and understood. Now it is revealed that placing simple elemental chromium under pressure suppresses its normal magnetic state and gives direct experimental access to the underlying quantum phase transition responsible for these changes.

The authors use nitrogen-vacancy centre magnetometry to explore layer number and magnetic field evolution of ferromagnetic and antiferromagnetic domains in the A-type antiferromagnet CrPS₄.

Skyrmionium, like the more well-known magnetic skyrmion, is a topological spin texture. It is characterized by ring shaped magnetic texture, where both inside and outside the magnetization is the same, yielding a topological charge of zero. Here, Yang et al demonstrate reversible control of skyrmioniums, switching between skyrmions and skyrmionium using electric currents.

Imaging the antiferromagnetic (AFM) domains facilitates the understanding and design of AFM spintronics but is still challenging. Here the authors show an imaging approach for antiphase domains in AFM Fe₂Mo₃O₈ by resonantly scattered coherent soft X-rays, which is also applicable to collinear antiferromagnets.

Topological spin textures are of technological interest due to their potential as a store of information. Here the authors experimentally demonstrate two distinct topological spin textures, tubular and incomplete skyrmions, and their mutual conversion in a ferromagnetic/ferromagnetic heterostructure.

Non-adiabatic spin-transfer torque in antiferromagnetically coupled ferrimagnets acts like a staggered magnetic field and can induce efficient domain wall motion.

Sub-micrometre spin waves are excited in anisotropic spin textures and they can propagate as 2D plane waves over several micrometres and as 1D waves along curved domain walls.

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.

Heavy-fermion materials have unusual electronic behavior due to a dual localized-itinerant character of 4f electrons. Here, by studying divalent EuRh₂Si₂, the authors gain insight into the electronic states of the trivalent heavy fermion system YbRh₂Si₂ and show that it experimentally demonstrates Luttinger’s theorem.

It was shown that the entanglement spectrum of topological systems is related to the energy spectrum of edge states, but only for gapped phases. Here the authors explain this relationship in terms of the wormhole effect in the path integral of the reduced density matrix and extend it beyond gapped phases.

In a Mn₃Sn/W epitaxial bilayer, spin–orbit torque induces the coherent rotation of spins, which can couple to microwave currents. Unlike in ferromagnets, the resulting conversion of AC current to DC voltage remains robust at higher frequencies, which may facilitate the development of high-speed electronic devices.

Recently, the quantum anomalous Hall effect has been successfully achieved in the intrinsic magnetic topological insulator MnBi₂Te₄, but zero-field quantization has proved difficult to achieve due to poor sample quality. Here, the authors report zero-field quantization and chiral edge states in five-septuple-layer MnBi₂Te₄.

The Tomonaga–Luttinger liquid framework can be used to describe 1D quantum systems, spanning fermions, bosons and anyons. In this Review, we discuss the various platforms that can host TLL states, including Josephson junctions, cold atoms and topological materials, and discuss the advances TLL theory can provide in quantum criticality, nonequilibrium dynamics and condensed-matter physics exploration.

A study establishes a scalable approach to engineer and characterize a many-body-localized discrete time crystal phase on a superconducting quantum processor.