Search

A study shows that in electron-doped Ba(Fe_1−xCo_x)₂As₂, the presence or absence of superconductivity and antiferromagnetism can be linked directly to changes in the Fermi surface—as measured by angle-resolved photoemission spectroscopy.

The authors study epitaxial thin films of the pyrochlore-sublattice compound LiTi2O4 by RIXS and ARPES. They observe cooperation between strong electron correlations and strong electron-phonon coupling, giving rise to a mobile polaronic ground state in which charge motion and lattice distortions are coupled.

The presence of excitonic instability and its relationship with a structural transition in Ta₂NiSe₅ has been debated. Chen et al. map out the electronic bands and lattice distortion across the semimetal-to-semiconductor transition with sulfur doping, revealing the crucial role of electron-phonon coupling.

A singularity in a material’s density of states at the Fermi energy can drive the formation of unconventional electronic phases. Here the authors show a Van Hove singularity is tunable across the Fermi energy in an oxide heterostructure, leading to enhanced electronic correlations.

Skyrmions—vortex-like spin textures—are conventionally only seen in materials that exhibit the right magnetic properties. Li et al.now create so-called artificial skyrmions using a cobalt disk embedded in a magnetized nickel film, thus presenting a platform for controlling skyrmions.

Electronic transport measurements in a magnetic field on the topological Dirac semimetal Cd₃As₂ identify the predicted Weyl orbits that weave Fermi arcs and bulk states together; the Weyl orbits enable transfer of chirality from one node to another, and open up the possibility of controlling topological properties electronically.

Spin-polarized carriers could show an extra Hall component when moving through certain real-space topological spin textures. Here, He et al. report an exchange bias experienced by the topological spin textures living at the interface between a topological insulator and an adjacent antiferromagnet, suggesting a chiral spin texture is induced.

Closely-spaced anisotropically-engineered single-domain nanomagnets may be exploited to encode and transmit binary information. Here, Gu et al. use time-resolved X-ray microscopy to image signal propagation at the intrinsic nanomagnetic switching limit in permalloy nanomagnet chains.

The authors report a modulation of the magnon spin current by electric polarization reversal.

Angle-resolved photoemission spectroscopy of CaNi₂ shows a band with vanishing dispersion across the full 3D Brillouin zone that is identified with the pyrochlore flat band as well as two additional flat bands that arise from multi-orbital interference of Ni d-electrons.

The authors study the non-centrosymmetric achiral material In_xTaS₂ by angle-resolved photoemission spectroscopy and quantum oscillations. They find that it hosts an “ideal” Kramers nodal line, well isolated at the Fermi level.

Excitonic quantum oscillations are observed in correlated electron–hole bilayers and quantum phase transitions are identified between excitonic insulator and bilayer quantum Hall states under strong magnetic fields.

Understanding the mechanism by which magnons—the quanta of spin waves—propagate is important for developing practical devices. Now it is shown that long-range dipole–dipole interactions mediate the propagation in a van der Waals antiferromagnet.

The formation of magnetic vortices such as skyrmions is hampered by the stochastic nature of thermal fluctuations. Here, the authors demonstrate that ultrafast dynamics in the initial stages of vortex formation can dominate the stochastic behaviour observed in the steady state.

A prototypical kagome metal with magnetic and topological properties is identified.

In BaFe₂As₂, the lattice couples strongly to the magnetic and electronic degrees of freedom, providing a way to control them. Here, by means of time-resolved X-ray scattering, the authors measure rapid lattice oscillations, which can induce changes in the material’s electronic and magnetic properties.

The authors experimentally realize the control of the topological charge of magnetic skyrmionic structures at room temperature in a Dzyaloshinskii-Moriya interaction (DMI) platform with spatially alternating signs. By modifying the DMI energy landscape through chemisorbed oxygen, a magnetic topological transition is realized.

A sufficiently strong magnetic field drives an electron system into the so-called extreme quantum limit. Zhang et al. demonstrate that in this regime, a Dirac semimetal acquires a robust plateau in the thermoelectric Hall conductivity, with a value independent of magnetic field or electron concentration.

A scalable spintronic device operating via spin–orbit transduction and magnetoelectric switching and using advanced quantum materials shows non-volatility and improved performance and energy efficiency compared with CMOS devices.

Nanoscale magnetic skyrmions that are generated in metallic multilayers using on-chip heating diffuse from hot to cold regions and can be thermoelectrically detected via the Nernst voltage.

Scanning tunnelling microscopy is used to reveal a new topological kagome magnet with an intrinsic Chern quantum phase, which shows a distinct Landau fan structure with a large Chern gap.

The intrinsic nature and dynamics of a Bloch point has not been verified so far. Here, Im et al. report the realization and dynamical character of steady-state Bloch points in the magnetic vortex cores in asymmetrically shaped Ni₈₀Fe₂₀ nanodisks.

The tunability of electronic properties is a central goal of research into topological semimetals. Here, the authors report Weyl nodal ring states in the magnetic semimetal EuGa₄ and link the nodal ring state to the observed large non-saturating magnetoresistance.

Angle-resolved photoemission spectroscopy shows that the superconducting critical temperature in optimally doped iron pnictide Ba(Fe_1−xCo_x)₂As₂ can be enhanced upon Na/K surface doping.

The atmospheric terminator region of WASP-39 b, a hot gas giant exoplanet, is inhomogeneous, despite past assumptions, with the evening terminator being hotter and thus probably clearer, and the morning terminator probably being cloudy and consequently cooler.

Topological magnetic monopoles are non-local spin textures that are robust to thermal and quantum fluctuations, but they are difficult to study at the nanoscale in real space. Now, soft X-ray vector ptycho-tomography is demonstrated to determine the three-dimensional magnetization vector and emergent magnetic field of such magnetic monopoles in a ferromagnetic meta-lattice.

Spin-orbit torques, arising in systems with strong spin-orbit interactions, have been a major avenue of research for the potential electric control of magnetization. Recently, unconventional spin-orbit torques, with spin polarizations aligned in atypical ways have garnered interest due to the numerous advantages offered compared to their conventional counterparts. Here, Xue et al investigate ‘type-x’ spin-orbit torque switching, demonstrating both unique spin polarizations, and field-free magnetization switching in Platinum/Cobalt multilayers.

High speed current induced domain wall motion is key to various spintronic applications, such as memory-storage. Here the authors show that the motion of chiral domain walls in Co/Gd bilayer structures is controlled by an exchange coupling torque that is maximized at the temperature where the Co and Gd angular momenta exactly balance each other

Spectroscopic measurements show how the features of the band structure related to the kagome lattice in CsV₃Sb₅ contribute to the observed strongly correlated phases.

Topological transition of a bubble to a skyrmion by the controlled magnetic monopoles injection in Fe/Gd magnetic multilayers. The magnetic monopoles injected from the top and bottom surfaces are topologically characterized by Q = −1 and Q = +1, respectively.

The magnetization of a cobalt thin film can be reversed by spin–orbit torques using picosecond electrical pulses that are generated by photoconductive switches.

In many cuprates the high temperature superconducting state competes with a charge ordered phase that has been difficult to investigate in detail. Here the authors show three-dimensional charge order can be stabilized in YBCO films and studied without using the high magnetic fields that are necessary in the bulk material.

Trilayer graphene was recently shown to exhibit superconductivity without a Moire pattern that had proved important in tuning superconductivity in bilayer graphene. Here, the authors explore correlated metallic phases and the pairing mechanism of superconductivity in trilayer graphene, and show that intervalley coherent fluctuations can act as a pairing glue, giving rise to chiral unconventional superconductivity.

Nanoscale magnetic devices play a key role in modern technologies but current applications involve only 2D structures like magnetic discs. Here the authors review recent progress in the fabrication and understanding of 3D magnetic nanostructures, enabling more diverse functionalities.

Tuning of the oscillations within a single nanodevice is a vital factor for harnessing them to neuromorphic computing. Herein, tuning of the oscillation properties of spin structures within a single permalloy circular disk achieved by manipulating the dimensionality of spin structures is directly observed by the time-resolved X-ray microscopy.

As indicated by direct band-structure measurements and calculations, tiny native imperfections in bilayer graphene are sufficient to cause the generation of coexisting massive and massless Dirac fermions. The massless spectrum is robust against strong electric fields and has a closed-arc topology consisting of a unique chiral pseudospin texture.

Worldwide pandemics of obesity and diabetes prompt an urgent need for new approaches to their prevention and cure. Here the authors present a CRISPR-based strategy that enhances the therapeutic potential of human adipocytes when implanted in obese mice.

HIV-1 infection is associated with persistent inflammation that can contribute to a variety of comorbidities. Luban and colleagues demonstrate that HIV-1 infection results in permanent depletion of innate lymphoid cells, leading to breakdown of gut barrier function and a feed-forward inflammation loop, which includes skewing of NK cells toward an inflammatory/memory phenotype.

The molecular basis of the basal tone generated by internal anal sphincters (IAS) is largely unknown. Here, the authors show that the tone arises from a global rise in intracellular Ca²⁺ in smooth muscle cells via a Ryanodine receptor-TMEM16A-L-type Ca²⁺channel-MLC kinase pathway, suggesting a potential therapy for IAS motility disorders.

The measurement of the total cross-section of proton–proton collisions is of fundamental importance for particle physics. Here, the first measurement of the inelastic cross-section is presented for proton–proton collisions at an energy of 7 teraelectronvolts using the ATLAS detector at the Large Hadron Collider.