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In electrostatically-gapped bilayer graphene, topologically-protected states can emerge at naturally occurring stacking domain walls even in the absence of a magnetic field. Here, the authors describe the interplay between such domain wall states and quantum Hall edge transport within the eight-fold degenerate zeroth Landau level of suspended bilayer graphene.

Quantum Hall liquids play host to a wide range of unusual physics. Here, the authors use an electronic Fabry-Pérot interferometer to observe modulations of a quantum Hall liquid’s area, which can offer a means to study the statistics of fractional charges.

Experiments show that when driven by electric currents, magnetic skyrmions experience transverse motion due to their topological charge — similar to the conventional Hall effect experienced by charged particles in a perpendicular magnetic field.

A 3D quantum Hall effect has been reported in Dirac semimetal ZrTe₅ due to a magnetic-field-driven Fermi surface instability. Here, the authors show evidence of quasi-quantized Hall response without Fermi surface instability, but they argue that it is due to the interplay of the intrinsic properties of ZrTe₅ electronic structure and Dirac semi-metallic character.

Valley dependent spin polarization called spin-valley locking appears in absence of magnetism but it is limited to rare examples of transition metal dichalcogenides. Here, the authors report evidence of spin-valley locking and stacked quantum Hall effect in a bulk Dirac semimetal BaMnSb₂.

Quantum point contacts are gate-tunable constrictions allowing for control of charge carrier transmission in 2D electron gases. Here, the authors fabricate a hBN/graphene/hBN van der Waals heterojunction to enable quantum point contact devices in the integer and fractional quantum Hall regimes.

Magnetic skyrmions are promising objects for future spintronic devices. However, a better understanding of their dynamics is required. Here, the authors show that in contrast to predictions the skyrmion Hall angle is independent of their diameter and motion is dominated by disorder and skyrmion-skyrmion interactions in the system.

The broken-symmetry edge states that are the hallmark of the quantum Hall effect in graphene have eluded spatial measurements. Here, the authors spatially map the quantum Hall broken-symmetry edge states using atomic force microscopy and show a gapped ground state proceeding from the bulk through to the quantum Hall edge boundary.

Control of magnetization is important for applications in spintronics. Now, the piezomagnetic effect allows strain to control the anomalous Hall effect in a metal at room temperature by rotating its antiferromagnetic order.

Controlling emission and propagation of acoustic waves offers new design opportunities for acoustic devices. Here the authors demonstrate such controls thanks to the emergence of a synthetic pseudo-spin in two-dimensional acoustic metamaterial.

Spin-hall nano-oscillators have potential for use in neuromorphic computing applications. Normally they are based around combination platinum and permalloy. Here, the authors combine a permalloy ferromagnet with a low magnetic damping ferrimagnet, leading to significantly improved performance.

Chen et al. developed a self-powered smart magnetoelastic stent for real-time hemodynamic monitoring and stenosis detection.

The kagome magnet Co₃Sn₂S₂ has complex magnetic behaviour and a topological band structure that yields a large anomalous Hall effect. Guguchia et al. find phase separation between ferro- and anti-ferromagnetic orders and that the volume-wise competition controls the anomalous Hall conductivity

What makes the phonons in cuprates become chiral, as measured by their thermal Hall effect, is an unresolved question. Here, the authors rule out two extrinsic mechanisms and argue that chirality comes from a coupling of acoustic phonons to the intrinsic excitations of the CuO₂ planes.

Conventional type 1 dendritic cells (cDC1) can boost the precursor exhausted T cell population thought to be essential for efficacy of immune checkpoint therapy. Here the authors enhance this cellular network using Flt3L to expand cDC1s and then map the movement of T cells and DCs between tumors and lymph nodes.

Direct measurement of the Berry curvature and the quantum metric of photonic modes in a high-finesse planar microcavity is achieved, enabling quantitative prediction of the independently measured anomalous Hall drift.

High-frequency elastic waves can propagate across local disorder and around sharp corners in nanoelectromechanical aluminium nitride membranes; this behaviour can be directly imaged using microwave microscopy.

Imaging studies show that topological protection in the quantum Hall state in graphene is undermined by edge reconstruction with a dissipation mechanism that comprises two distinct and spatially separated processes—work generation and entropy generation.

Propagating spin waves known as magnons are expected to carry a dipole moment in the quantum Hall regime. Now, this moment has been detected, demonstrating that the degrees of freedom of spin and charge are entangled in quantum Hall magnons.

Three tunable quantum Hall broken-symmetry states in charge-neutral graphene are identified by visualizing their lattice-scale order with scanning tunnelling microscopy and spectroscopy.

Quantum Hall phases have chiral edge modes, which could be used to explore and exploit the quantum properties of electrons. Interactions in these edge states lead to relaxation and decoherence, hindering any realistic exploitation. Here the authors observe spectroscopically the decay and revival of the excitation created by injection of an electron into the edge mode. Their results confirm phase-coherent transport and quantify the effect of dissipation-induced decoherence.

Pseudaminic acids (Pse) are a family of carbohydrates found within bacterial lipopolysaccharides, capsular polysaccharides and glycoproteins. Now, monoclonal antibodies have been developed that recognize diverse Pse across several bacterial species, enabling mapping of the Pse glycoproteome and demonstrating therapeutic potential against multidrug-resistant Acinetobacter baumanii in in vitro and in vivo infection models.

Not only the area of Néel skyrmions, but also their number and sign contribute to their Hall resistivity.

Conductance quantization is the hallmark of non-interacting confined systems. The authors show that the quantization in graphene nanoconstrictions with low edge disorder is suppressed in the quantum Hall regime. This is explained by the addition of new conductance channels due to electrostatic screening.

Large-area graphene devices synthesized by chemical vapour deposition are used to develop electrical resistance standards, based on the quantum Hall effect, with state-of-the-art accuracy and under an extended range of experimental conditions of magnetic field, temperature and current.

Manipulating spin currents in graphene by the spin–orbit interaction is important for many technological developments. Here, the authors show that the presence of residual metallic adatoms in chemical vapour deposition graphene enhances its spin–orbit coupling by three orders of magnitude.

There is a long-standing experimental effort to observe field-induced correlated states in three-dimensional materials. Here, the authors observe an unconventional Hall response in the quantum limit of the bulk semimetal HfTe₅ with a plateau-like feature in the Hall conductivity.

The synchronization of nine nanoconstriction spin Hall nano-oscillators brings spin-based oscillators closer to the power and noise requirements needed for practical applications.

Theories predict a large thermopower and a quantized thermoelectric Hall conductivity in topological semimetals. Here, the authors observe an ultrahigh longitudinal thermopower and a giant power factor attributed to the quantized thermoelectric Hall effect in a Weyl semimetal TaP.

A martensitic alloy with a tensile strength exceeding 3 GPa and a fracture elongation of 5.13% is developed. These mechanical properties arise from interface complexes interacting with dense dislocation networks, which is a mechanism shown to be applicable to other compositions.

The topological Hall Effect (THE) enhances our understanding of chiral spin textures such as skyrmions, but important aspects of the relationship are still unclear. Here the authors present a comprehensive picture for the spin texture evolution and corresponding THE signatures in a multilayer film using Hall transport and magnetic imaging.

Previous work has proposed that the anomalous and topological Hall effects, associated with Weyl nodes, should have a signature in optical conductivity. Here, using THz optical spectroscopy, the authors assign these two effects to optical conductivity resonances, arising near band anti-crossings, in thin films of MnGe.

The evolution of the quantum Hall state from bulk spectrum to edge state remains obscure. Here, Patlatiuk and Scheller et al. observe magnetic compression against a hard edge followed by motion into the bulk and depopulation of the integer quantum Hall edge states, in agreement with the bulk-to-edge correspondence.

Topological surface states can lose their protection in many ways but the subtle mechanisms remain far from well understood. Here, Taskin et al. report a novel planar Hall effect in dual-gated Bi_2−x Sb _x Te₃ thin films, originating from anisotropic lifting of time reversal symmetry protection by an in-plane magnetic field.

In the superconducting phase of niobium nitride the spin Hall effect is mediated by quasiparticles. Decreasing the spin injection current causes the inverse spin Hall signal to become 2,000 times larger in this phase than in the normal state.

The Weyl semimetal Co\(_{3}\)Sn\(_{2}\)S\(_{2}\) exhibits a combination of magnetic ordering with a large anomalous Hall effect. Lachman et al. find an intrinsic exchange bias of this anomalous Hall effect and attribute it to the coexistence of ferromagnetism and spin glass behaviour.

A proposed theoretical explanation for the electronic behaviour of moiré graphene is the coexistence of light and heavy electrons. Now local thermoelectric measurements hint that this model could be accurate.

Interferometers can probe the wave-nature and exchange statistics of indistinguishable particles. Quantum Hall interferometers from graphite-encapsulated graphene heterostructures now enable the observation of the Aharonov–Bohm effect and of robust fractional quantum Hall states.

Graviton modes are long-wavelength neutral collective excitations of fractional quantum Hall fluids that are analogous to gravitons. Here the authors develop a microscopic theory of multiple graviton modes and show that they are associated with geometric fluctuations of hierarchical conformal Hilbert subspaces.

Experiments show that when driven by electric currents, magnetic skyrmions experience transverse motion due to their topological charge — similar to the conventional Hall effect experienced by charged particles in a perpendicular magnetic field.

Quantum Hall states are observed in monolayer graphene at even-denominator fractional filling of the lowest Landau level. This is linked to transitions in the spin and valley structure of the ground state.

The integration of a TMDC monolayer into a high-Q microcavity enables the observation of optical valley Hall effect.

The spin Hall effect plays a central role in generating and manipulating spin currents, but its magnitude is ultimately fixed by spin–orbit coupling effects. It is now shown that the spin-Hall-effect angle can be tuned electrically in GaAs.

Here the authors compare genetic testing strategies in rare movement disorders, improve diagnostic yield with genome analysis, and establish CD99L2 as an X-linked spastic ataxia gene, showing that CD99L2–CAPN1 signaling disruption likely drives neurodegeneration.

One way of producing Majorana fermions for topological quantum computing is to induce superconductivity in other topological states. Here, the proximity effect does this for the quantum spin Hall effect state in a 2D material.