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Weyl semimetals exhibit Berry flux monopoles in momentum-space, but direct experimental evidence has remained elusive. Here, the authors reveal topologically non-trivial winding of the orbital-angular-momentum at the Weyl nodes and a chirality-dependent spin-angular-momentum of the Weyl bands, as a direct signature of the Berry flux monopoles in TaAs.

Experimental signatures of a Berry phase for composite fermions in the fractional quantum Hall effect provide support for the predictions that these composite fermions are Dirac particles.

The dynamical axion quasiparticle, which is directly analogous to the hypothetical fundamental axion particle, is observed in two-dimensional MnBi₂Te₄, and has implications for quantum chromodynamics, cosmology and string theory.

Topological magnetic semimetals can realise large intrinsic anomalous Hall effects using the characteristics of their electronic band structure and Berry curvature. Here, the authors predict an anomalous Hall effect for cubic CrPt₃ using first principle calculations and confirm the results experimentally.

The fractional quantum Hall effect occurs when electrons move in Landau levels. In this study, using a theoretical flat-band lattice model, the fractional quantum Hall effect is observed in the presence of repulsive interactions when the band is one third full and in the absence of Landau levels.

Recent experiments suggest the possibility of realizing fractional Chern insulators in twisted transition metal dichalcogenides. Here, the authors present numerics revealing a robust non-Abelian zero magnetic-field state that may be realized in twisted bilayer MoTe2 in a specific parameter range.

In all experimentally observed Weyl semimetals so far, the Weyl points always appear in pairs in the momentum space. Here, the authors report one unpaired Weyl point without surface Fermi arc emerging at the center of the Brillouin zone, which is surrounded by charged Weyl nodal walls in PtGa.

Bloch oscillations (BO) are intrinsically related to the geometry and topological properties of the underlying band structure. Here, Di Liberto et al. predict a unique topological effect manifested in the BOs of higher-order topological insulators through the interplay of non-Abelian Berry curvature and quantized Wilson loops.

The two-dimensional atomic layers of black phosphorus may be exfoliated to create devices with desirable electronic transport properties. Here, the authors observe two-dimensional quantum transport in black phosphorus quantum wells, protected from oxidation by encapsulation in a polymer layer.

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.

Phase transitions in topologically non-trivial systems are characterized by changes of topological invariants, rather than conventional order parameters. Here, the authors propose a real-space topological phase transition upon pair annihilation of emergent monopoles inherent in chiral magnet MnGe.

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.

High-harmonic generation from the Dirac-like surface state of a topological insulator is separated from bulk contributions and continuously tuned by the carrier-envelope phase of the driving lightwave.

The transport behavior of the carriers residing in the lowest Landau level is hard to observe in most topological materials. Here, Liu et al. report a surprising angular dependence of the interlayer magnetoresistivity and Hall conductivity arising from the lowest Landau level under high magnetic field in type II Weyl semimetal YbMnBi₂.

Ferromagnetic systems rarely display a large or non-saturating magnetoresistance, due to the low Fermi velocity of the predominant charge carrier. Here, the authors show that MnBi, a ferromagnet, bucks this trend, showing both large and non-saturating magnetoresistance, and high charge carrier motilities.

The quark structure of the f₀(980) hadron is still unknown after 50 years of its discovery. Here, the CMS Collaboration reports a measurement of the elliptic flow of the f₀(980) state in proton-lead collisions at a nucleon-nucleon centre-of-mass energy of 8.16 TeV, providing strong evidence that the state is an ordinary meson.

The possibility of tuning the shape of the Weyl nodes in topological magnets could open an avenue towards engineering their electrical behaviour. Here, the authors report the tuning of Weyl nodes and associated magnetotransport in MnSb₂Te₄ by diffusion-controlled ionic hydrogen insertion.

Exploitation of the valley electronic structure of transition metal dichalcogenides with exciton–polaritons is an elusive challenge. Now, valley-polarized exciton–polaritons in monolayers of MoS₂ have been demonstrated.

Surface conductance variations in non-vegetated salt flats are similar to those in vegetated ecosystems and in an idealized boundary layer model. This suggests that soil moisture, and not vapour pressure deficit, controls surface conductance variations.

The evidence of topological origin for the recently observed anomalous Hall effect remains elusive. Here, the authors report that the resonance of the optical Hall conductivity resulted from topological electronic structure gives rise to the large intrinsic anomalous Hall effect in the magnetic Weyl semimetal Co₃Sn₂S₂.

While topological states are often characterized by their global properties related to the topological invariants, the introduced real-space topological markers provide new insights to these states.

Bloch wavefunctions of two types of hole in gallium arsenide are reconstructed by measuring the polarization of light emitted by collisions of electrons and holes accelerated by a terahertz laser.

A series of transport experiments on lanthanum antimonide reveal a plateau in its resistivity and an extremely large magnetoresistance that are consistent with topologically protected electronic states.

A significant enhancement in the effective mass of Dirac-like quasiparticles residing near a nodal loop in the electronic band structure provides evidence for strong correlation effects in a topological semimetal.

Probing topological orders in many-body systems remains a major challenge, which requires bulk-edge correspondence. Here, Grusdt et al.present an approach to show that fractional charges can be directly probed in the bulk of fractional quantum Hall systems using mobile impurities through interferometric measurements.

Superconducting quantum circuits are used to directly observe and characterize topological phase transitions; this approach promises to be a powerful and general platform for characterizing topological phenomena in quantum systems.

Magnetotransport measurements show that ZrTe₅ exhibits an anomalous Hall effect without magnetic ordering, a signature of Berry curvature introduced by Weyl nodes. This indicates that ZrTe₅ may be a Weyl semimetal, even though this was not predicted.

Cold atom systems are a playground for new quantum phenomena, one of which might be Majorana fermions – particles that are their own antiparticles. Qu et al. show how a topological superfluid with Fulde–Ferrell pairing might emerge in a spin–orbit-coupled degenerate gas, which could support Majorana fermions.

We report a high anomalous Nernst thermopower (\(S_{yx}^A\)) -value of ~6.0 µV K⁻¹ at room temperature in the ferromagnetic topological Heusler compound Co₂MnGa. The measured value is seven-times larger than any anomalous Nernst thermopower value ever reported for a conventional ferromagnet. The high anomalous Nernst effect originates from a large net Berry curvature near the Fermi level associated with nodal lines and Weyl points.

Using well-calibrated statistical methods the authors jointly analyze Undiagnosed Diseases Network genomes, identifying known and novel disease genes. Software is publicly available to support future cross-cohort rare disease discovery efforts.

A three-dimensional topological insulator nanowire is predicted to display gapped one-dimensional surface transport properties. Here, the authors demonstrate this experimentally, observing characteristic quantum oscillations in conductance in (Bi1.33Sb0.67)Se3 nanowires under an applied magnetic field.

Non-equilibrium signatures of topology—the appearance, movement and annihilation of vortices in a cold-atom system—are identified, showing that topological phase can emerge dynamically from a non-topological state.

The bulk photovoltaics refers to an effect whereby electrons move directionally in non-centrosymmetric crystals upon light radiation. Here, Nakamura et al. observe this effect in a ferroelectric organic charge-transfer complex, which shows large diffusion distance of photogenerated electrons over 200 µm.

Huang et al. study fractional quantum Hall (fQH) states in high-quality GaAs/AlGaAs samples. They report evidence for a fQH state at filling factor ν = 9/11, which they associate with the formation of six-flux composite fermions.

Wheat stem rust resistance gene Sr6-mediated resistance is enhanced at lower temperatures whereas Sr13 and Sr21 resistances are enhanced at higher temperatures. Here, the authors clone Sr6 and show the divergent molecular pathways governing temperature-dependent resistance among these genes.

Edge current quantization in the integer quantum Hall effect is understood to arise due to noninteracting electrons circulating an incompressible insulating bulk. Here, the authors evidence compressible metal-like bulk behaviour in GaAs/AlGaAs Hall bars consistent with electronic interactions.