Spin waves can carry information that could be used for data processing, but producing and controlling them can be challenging. Now it is possible to generate short-wavelength coherent spin waves that can travel at high speed over a long distance.

Magnonics is a research field complementary to spintronics, in which the quanta of spin waves (magnons) replace electrons as information carriers, promising lower dissipation1,2,3. The development of ultrafast, nanoscale magnonic logic circuits calls for new tools and materials to generate coherent spin waves with frequencies as high and wavelengths as short as possible4,5. Antiferromagnets can host

Using pressure to tune the balance of interactions in a new class of kagome superconductor results in a surprising competition between states — and hints at an unusual, electronically intertwined order.

The United Nations Sustainable Development Goals outline a roadmap towards a more equitable future for humanity. Along with other scientists, physicists have long made valuable contributions to this endeavour.

The flagella of microorganisms have provided inspiration for many synthetic devices, but they’re typically not easy to produce. A new class of swimmer makes it look simple by spontaneously growing a tail that it can whip to self-propel.

Excitons, quasiparticles of electrons and holes bound by Coulombic attraction, are created transiently by light and play an important role in optoelectronics, photovoltaics and photosynthesis. They are also predicted to form spontaneously in a small-gap semiconductor or a semimetal, leading to a Bose–Einstein condensate at low temperature, but there has not been any direct evidence of this effect so

The design of artificial microswimmers is often inspired by the strategies of natural microorganisms. Many of these creatures exploit the fact that elasticity breaks the time-reversal symmetry of motion at low Reynolds numbers, but this principle has been notably absent from model systems of active, self-propelled microswimmers. Here we introduce a class of microswimmers that spontaneously self-assembles

Initially used to measure the brightness of radio sources, the jansky has spread to other areas of astronomy, as Natasha Hurley-Walker recounts.

Ensuring that a manuscript is vetted by experts is an important part of the editorial process, so we strive to choose the best reviewers to help us do this. How we manage the selection is a nuanced process.

Recently, several quantum machine learning algorithms have been proposed that may offer quantum speed-ups over their classical counterparts. Most of these algorithms are either heuristic or assume that data can be accessed quantum-mechanically, making it unclear whether a quantum advantage can be proven without resorting to strong assumptions. Here we construct a classification problem with which we

Single-molecule experiments can now quantify the surface forces that compete to package tethered DNA into a protein-rich condensate — providing much-needed mechanistic insight into the phase behaviour of the entangled genome in the nucleus.

Turing’s reaction–diffusion theory of morphogenesis has been very successful for understanding macroscopic patterns within complex objects ranging from biological systems to sand dunes. However, Turing patterns on microscopic length scales are extremely rare. Here we show that a strained atomic bismuth monolayer assembled on the surface of NbSe2—and subject to interatomic interactions and kinetics—displays

Quantum computing can be realized with numerous different hardware platforms and computational protocols. A highly promising, and potentially scalable, idea is to combine a photonic platform with measurement-induced quantum information processing. In this approach, gate operations can be implemented through optical measurements on a multipartite entangled quantum state—a so-called cluster state. Previously

Interactions between liquids and surfaces generate forces1,2 that are crucial for many processes in biology, physics and engineering, including the motion of insects on the surface of water3, modulation of the material properties of spider silk4 and self-assembly of microstructures5. Recent studies have shown that cells assemble biomolecular condensates via phase separation6. In the nucleus, these

Cells moving on microprinted tracks reveal a preference for regions that they have already visited, suggesting an update to a century of dynamical models for cell trajectories.

The ATLAS Collaboration has confirmed with top quark events that the coupling of charged leptons to the weak interaction is universal — showcasing the feasibility of performing high-precision electroweak measurements at proton–proton colliders.

The Vlasov equation describes collisionless plasmas in the continuum limit and applies to many fundamental plasma energization phenomena. Because this equation governs the evolution of plasma in six-dimensional phase space, studies of its structure have mostly been limited to numerical or analytical methods. Here terms of the Vlasov equation are determined from observations of electron phase-space

The standard model of particle physics encapsulates our best current understanding of physics at the smallest scales. A fundamental axiom of this theory is the universality of the couplings of the different generations of leptons to the electroweak gauge bosons. The measurement of the ratio of the decay rate of W bosons to τ leptons and muons, R(τ/μ), constitutes an important test of this axiom. Using

Nonlinearity and topology are both linked to symmetries, but what happens when the two are combined is not a trivial question. In a nonlinear photonic higher-order topological insulator, solitons localize on the corners together with the topological modes.

Quantum antiferromagnets are of broad interest in condensed-matter physics as they provide a platform for studying exotic many-body states1 including spin liquids2 and high-temperature superconductors3. Here we report on the creation of a one-dimensional Heisenberg antiferromagnet with ultracold bosons. In a two-component Bose–Hubbard system, we switch the sign of the spin-exchange interaction and

Leptons with essentially the same properties apart from their mass are grouped into three families (or flavours). The number of leptons of each flavour is conserved in interactions, but this is not imposed by fundamental principles. Since the formulation of the standard model of particle physics, the observation of flavour oscillations among neutrinos has shown that lepton flavour is not conserved

Higher-order topological insulators are a novel topological phase beyond the framework of conventional bulk–boundary correspondence1,2. In these peculiar systems, the topologically non-trivial boundary modes are characterized by a co-dimension of at least two3,4. Despite several promising preliminary considerations regarding the impact of nonlinearity in such systems5,6, the flourishing field of experimental

Light pulses transiently change a metal to an insulator by unveiling a hidden ordered state.

Quantum computers promise the ability to solve problems that are intractable in the classical setting1, but in many cases this is not rigorously proven. It is often possible to establish a provable theoretical advantage for quantum computations by restricting the computational power2,3,4,5,6,7,8. In multiple cases, quantum advantage over these restricted models was demonstrated experimentally9,10,11

In correlated electron materials, multiple electronic phases may appear next to each other in their phase diagram, and these can be tuned, for example, by applying static pressure or chemical doping1,2,3. These perturbations modify the subtle balance between the electron transfer energy and Coulomb repulsion between electrons. It is, therefore, tempting to explore whether new states of matter can be

Entanglement is the crucial ingredient of quantum many-body physics, and characterizing and quantifying entanglement in the closed-system dynamics of quantum simulators remains a challenge in today’s era of intermediate-scale quantum devices. Here we discuss an efficient tomographic protocol for reconstructing reduced density matrices and entanglement spectra for spin systems. The key step is a parametrization

The transport of polymers across nanoscale pores underpins many biological processes, such as the ejection of bacteriophage DNA into a host cell and the transfer of genes between bacteria. The movement of polymers into and out of confinement is also the basis for a wide range of sensing technologies used for single-molecule detection and sequencing. Acquiring an accurate understanding of the translocation

Many aspects of gauge theories — such as the one underlying quantum chromodynamics, which describes quark physics — evade common numerical methods. Tensor networks are getting closer to a solution, having successfully tackled the related problem of a three-dimensional quantum link model.

The interplay of different electronic phases underlies the physics of unconventional superconductors. One of the most intriguing examples is a high-temperature superconductor, FeTe1 – xSex (refs. 1,2,3,4,5,6,7,8,9,10,11). This superconductor undergoes both a topological transition3,4, linked to the electronic band inversion, and an electronic nematic phase transition, associated with rotation symmetry

The two-fluid model of superfluids predicts a second, quantum mechanical form of sound. Ultracold atom experiments have now measured second sound in the unusual two-dimensional superfluid described by the Berezinskii–Kosterlitz–Thouless transition.

Introducing non-local effects to metamaterials increases the complexity of their dispersion relation, which allows carefully designed elastic structures to mimic the peculiar roton behaviour of correlated quantum superfluids.

A single equation can describe how fluids flow across a wide range of length scales, from ocean currents to swimming algae. The difference merely lies in the Reynolds number, says Julia Yeomans.

Articulating the case for investment in large-scale physics projects is rarely straightforward. If scientists are to continue to do so effectively in the future, they must learn to grapple with a host of issues that they have perhaps been lucky to be shielded from in the past.

High-order harmonics of laser pulses yield spectral components with shorter wavelength and duration and tighter focus than the original pulse. Precise spatiotemporal characterization of this radiation from a relativistic plasma mirror is relevant for ultrafast science.

Reaching light intensities above 1025 W cm−2 and up to the Schwinger limit of order 1029 W cm−2 would enable the testing of fundamental predictions of quantum electrodynamics. A promising—yet challenging—approach to achieve such extreme fields consists in reflecting a high-power femtosecond laser pulse off a curved relativistic mirror. This enhances the intensity of the reflected beam by simultaneously

Undergraduate labs are more effective and more positive for students if they encourage investigation and decision-making, not verification of textbook concepts.

Recent measurements of observables related to proton and neutron spin properties at low energies are in disagreement with the available theoretical predictions, and continue to challenge nuclear experimentalists and theorists alike.

Understanding the nucleon spin structure in the regime where the strong interaction becomes truly strong poses a challenge to both experiment and theory. At energy scales below the nucleon mass of about 1 GeV, the intense interaction among the quarks and gluons inside the nucleon makes them highly correlated. Their coherent behaviour causes the emergence of effective degrees of freedom, requiring the

Thermalization is the inevitable fate of many complex quantum systems, whose dynamics allow them to fully explore the vast configuration space regardless of the initial state—the behaviour known as quantum ergodicity. In a quest for experimental realizations of coherent long-time dynamics, efforts have focused on ergodicity-breaking mechanisms, such as integrability and localization. The recent discovery

Gradients in fluid viscosity characterize microbiomes ranging from mucus layers on marine organisms1 and human viscera2,3 to biofilms4. Although such environments are widely recognized for their protective effects against pathogens and their ability to influence cell motility2,5, the physical mechanisms regulating cell transport in viscosity gradients remain elusive6,7,8, primarily due to a lack of

On the face of it, characterizing quantum dynamics in the exponentially large Hilbert space of a many-body system might require prohibitively many experiments. In fact, the locality of physical interactions means that it can be done efficiently.

Learning the Hamiltonian that describes interactions in a quantum system is an important task in both condensed-matter physics and the verification of quantum technologies. Its classical analogue arises as a central problem in machine learning known as learning Boltzmann machines. Previously, the best known methods for quantum Hamiltonian learning with provable performance guarantees required a number

A life-or-death choice determines the fate of reproductive cells. It has long been assumed that the choice is genetically regulated, but it now seems that the decision may instead be controlled by intracellular pressure.

A type of polar self-propelled particle generates a torque that makes it naturally drawn to higher-density areas. The collective behaviour this induces in assemblies of particles constitutes a new form of phase separation in active fluids.

Studies of active matter, from molecular assemblies to animal groups, have revealed two broad classes of behaviour: a tendency to align yields orientational order and collective motion, whereas particle repulsion leads to self-trapping and motility-induced phase separation. Here we report a third class of behaviour: orientational interactions that produce active phase separation. Combining theory and

Oocytes are large cells that develop into an embryo upon fertilization1. As interconnected germ cells mature into oocytes, some of them grow—typically at the expense of others that undergo cell death2,3,4. We present evidence that in the nematode Caenorhabditis elegans, this cell-fate decision is mechanical and related to tissue hydraulics. An analysis of germ cell volumes and material fluxes identifies

At high pressures, simple metals such as potassium have a rich phase diagram including an insulating electride phase in which electrons have a localized, anionic character. Measurements in the liquid phase have shown a transition between two states, but experimental challenges have prevented detailed thermodynamic measurements. Using potassium as an example, we present numerical evidence that the liquid–liquid

A Correction to this paper has been published: https://doi.org/10.1038/s41567-021-01261-9.

Quantum gates on trapped ions may be quicker and more reliable owing to squeezing of their vibrational motion. A threefold drop in operation time shows potential for applications in quantum technologies.

In the class of materials called spin liquids1,2,3, a magnetically ordered state cannot be attained even at millikelvin temperatures because of conflicting constraints on each spin; for example, from geometric or exchange frustration. The resulting quantum spin-liquid state is currently of intense interest because it exhibits unusual excitations as well as wave-function entanglement. The layered insulator

A major challenge in developing topological superconductors for implementing topological quantum computing is their characterization and control. It has been proposed that a p-wave-gapped topological superconductor can be fabricated with single-atom precision by assembling chains of magnetic atoms on s-wave superconductors with spin–orbit coupling. Here we analyse Bogoliubov quasiparticle interference

Strong and precisely controlled interactions between quantum objects are essential for quantum information processing1,2, simulation3 and sensing4,5, and for the formation of exotic quantum matter6. A well-established paradigm for coupling otherwise weakly interacting quantum objects is to use auxiliary bosonic quantum excitations to mediate the interactions. Important examples include photon-mediated

The recent measurement of the muon’s anomalous magnetic moment increases the tension with predictions from theory. Or does it?

As the namesake of a variety of constants, distributions and equations, Ludwig Boltzmann has earned his place in the physics hall of fame. But as Ankita Anirban reveals, he cannot take sole credit for the most famous constant bearing his name.

Robustness against perturbations lies at the heart of topological phenomena. If, however, a perturbation such as disorder becomes dominant, it may cause a topological phase transition between topologically non-trivial and trivial phases. Here we experimentally reveal the competition and interplay between topology and quasi-periodic disorder in a Thouless pump realized with ultracold atoms in an optical

As Hamiltonian models underpin the study and analysis of physical and chemical processes, it is crucial that they are faithful to the system they represent. However, formulating and testing candidate Hamiltonians for quantum systems from experimental data is difficult, because one cannot directly observe which interactions are present. Here we propose and demonstrate an automated protocol to overcome

Measurements of isotope ratios are predominantly made with reference to standard specimens that have been characterized in the past. In the 1950s, the carbon isotope ratio was referenced to a belemnite sample collected by Heinz Lowenstam and Harold Urey1 in South Carolina’s PeeDee region. Due to exhaustion of the sample since then, reference materials that are traceable to the original artefact are

Semiconductor heterostructures1 and ultracold neutral atomic lattices2 capture many of the essential properties of one-dimensional electronic systems. However, fully one-dimensional superlattices are highly challenging to fabricate in the solid state due to the inherently small length scales involved. Conductive atomic force microscope lithography applied to an oxide interface can create ballistic

The strong Ising spin–orbit coupling in certain two-dimensional transition metal dichalcogenides can profoundly affect the superconducting state in few-layer samples. For example, in NbSe2, this effect combines with the reduced dimensionality to stabilize the superconducting state against magnetic fields up to ~35 T, and could lead to topological superconductivity. Here we report a two-fold rotational

Measuring the spin structure of protons and neutrons tests our understanding of how they arise from quarks and gluons, the fundamental building blocks of nuclear matter. At long distances, the coupling constant of the strong interaction becomes large, requiring non-perturbative methods to calculate quantum chromodynamics processes, such as lattice gauge theory or effective field theories. Here we report