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Transition of superfluid to insulator is observed in the layer-imbalanced regime of bilayer magnetoexcitons.

The dynamics of hole-conjugated fractional quantum Hall states is poorly understood due to the limitations of current experimental probes. Here the authors study the high-frequency dynamics of edge modes at filling factor 2/3, precisely identifying the tunneling charge and damping of constituent charge modes.

One of the many exotic characteristics of systems that exhibit the fractional quantum Hall effect is the presence of chiral edge modes that carry energy but no net charge. Gurman et al.demonstrate the use of quantum dots to transform this energy into a measurable current, enabling them to better probe these modes.

Monolayer graphene can support the quantum Hall effect up to room temperature. Here, the authors provide evidence that graphene encapsulated in hexagonal boron nitride realizes a novel transport regime where dissipation in the quantum Hall phase is mediated predominantly by electron-phonon scattering rather than disorder scattering.

Electronic systems with inverted band structures can support exotic topological insulator and exciton condensate states. Here, the authors demonstrate the formation of a helical exciton condensate in quantum Hall bilayers, and a quark-like quasiparticle confinement-deconfinement transition.

A superconductor–graphene junction is shown to exhibit the quantum Hall effect, with the chemical potential of the edge state displaying a sign reversal. Such a system could provide a platform for observing isolated non-Abelian anyonic zero modes.

Electron pairing is a rare phenomenon which can result in exotic behaviour such as superconductivity. Here, the authors evidence robust electron pairing in the quantum Hall edge states of a Fabry–Perot interferometer via Aharonov–Bohm conductance oscillations and quantum shot noise measurements.

Spin–orbit torques could enable a new generation of low-power electrically controlled memory devices. Here, the authors experimentally disentangle the spin-Hall effect and inverse spin-galvanic effect contributions to the relativistic spin torques in a room temperature Fe/(Ga,Mn)As bilayer.

A technique that allows the electrical detection of spin-polarized transport in semiconductors without disturbing the spin-polarized current or using magnetic elements has now been demonstrated. The approach could lead to the integration of spintronics elements into semiconductor microelectronic circuits.

The topological Hall effect usually results from a static scalar spin chirality. Here, through a combination of neutron scattering and transport measurements, Baral et al. demonstrate the emergence of a room temperature topological Hall effect due to dynamic scalar spin chirality in a topologically non-trivial phase in Fe3Ga4

Graphene on boron nitride gives rise to a moiré superlattice displaying the Hofstadter butterfly: a fractal dependence of energy bands on external magnetic fields. Now, by means of capacitance spectroscopy, further aspects of this system are revealed—most notably, suppression of quantum Hall antiferromagnetism at particular commensurate magnetic fluxes.

Recently, anyonic statistics were observed in collision experiments on fractional quantum Hall states. Here the authors report signatures of anyonic statistics in the integer quantum Hall state with two copropagating channels, where electrons are split into fractional charges by inter-channel interaction.

Excitonic pairing in fractional quantum Hall states shows two new quantum phases, including a fractional exciton condensate and an unusual type of exciton that obeys fermionic or anyonic quantum statistics.

Skyrmion crystals, where skyrmions are arranged close packed in a triangular lattice arise due to the superposition of three magnetic spin spirals, each with a distinct wave vector, Q. Such skrymion crystals have been found in a diverse array of materials. Here, Park et al find a short wavelength (or dense skyrmion) limit of this skyrmion crystal structure in Co1/3TaS2, a metallic triangular lattice antiferromagnet, in the form of a triple Q magnetic ordering, with four magnetic sublattices.’

Rhombohedral tetralayer graphene aligned to a hexagonal boron nitride substrate hosts gate-tunable superconductivity and quantized anomalous Hall states, and thermodynamic compressibility measurements further show a fractional Chern insulator at zero magnetic field, paving the way for new hybrid interfaces between superconductors and topological edge states.

We show that domain walls in minimally twisted bilayer graphene support exceptionally robust proximity superconductivity in the quantum Hall regime.

Non-Hermitian systems can be described in terms of gain and loss with a coupled environment—a hard feature to tune in quantum devices. Now an experiment shows non-Hermitian topology in a quantum Hall ring without relying on gain and loss.

Previous measurements of interferometers based on quantum Hall (QH) edge channels have suggested potential electron pairing effects. Here, the authors investigate the coupling between QH edge channels in graphene Aharonov-Bohm (AB) interferometers, proposing a possible single-particle explanation for the apparent interference phase jumps and AB frequency doubling.

Excitations of the fractional quantum Hall states are of great interest because they obey anyonic statistics, but electronic interferometers give contrasting results about their quantum coherence. Here the authors use novel two-particle time-domain interferometry to show that quantum coherence is indeed preserved.

2D transition metal ditellurides exhibit nontrivial topological phases, but the controlled bottom-up synthesis of these materials is still challenging. Here, the authors report the layer-by-layer growth of large-area bilayer and trilayer 1T’ MoTe2 films, showing thickness-dependent ferroelectricity and nonlinear Hall effect.

The properties of edge states at the boundary between a quantum Hall insulator and a superconductor have recently been under scrutiny. Here, the authors find theoretically that Andreev reflection of an edge state is possible only if the superconductor is in the disordered limit, leading to stochastic edge state conductance and providing an explanation of a recent experiment.

Hybrid perovskites exhibit long carrier diffusion lengths and lifetimes. Here, Chen et al. show experimentally that carrier recombination in perovskites is far from Langevin and closer to the best direct-bandgap semiconductors, which can be explained by the dipolar polaronic nature of charge carriers.

The insertion of thin layers of cobalt can stabilize β-tungsten under back-end-of-line thermal constraints, allowing a 64-kb spin–orbit torque magnetic random-access memory to be fabricated that offers a spin–orbit torque switching of 1 ns, data retention of more than 10 years and a tunnelling magnetoresistance of 146%.

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.

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.

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.

Enhanced spin-charge conversion in graphene is realized by proximity coupling to WS₂ and electric-field tunability is demonstrated.

Previous studies of skyrmions in thin film architectures have shown widely-varying magnitudes of the topological Hall effect. Here, Raju et al. show that this variation follows a power-law behaviour driven by chiral spin fluctuations at the phase transition between isolated and lattice skyrmions.

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.

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.

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

High-mobility graphene can play host to exciton polaritons—hybrid matter–light particles, which can form into a state known as a quantum Hall polariton fluid. Here, the authors show that electron–electron interactions can act to destabilize this state and lead to the formation of a modulated phase.

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.

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.

The APOE-ε4 allele is the strongest genetic risk factor for late-onset Alzheimer’s disease, but it is not deterministic. Here, the authors show that common genetic variation changes how APOE-ε4 influences cognition.

Magneto-oscillations have revealed many interesting phenomena in graphene and quantum Hall systems, but they are typically measured at low currents and in equilibrium. Here, the authors report several non-equilibrium quantum effects observed in magneto-oscillations in graphene at high currents.

Guided by density functional theory, a commercially viable refractory alloy is developed, which exhibits excellent room-temperature ductility and strength, and high strength at elevated temperatures.

An electronic double layer, subjected to a high magnetic field, can form an exciton condensate: a Bose–Einstein condensate of Coulomb-bound electron–hole pairs. Now, exciton condensation is reported for a graphene/boron-nitride/graphene structure.

Encapsulated few-layer InSe exhibits a remarkably high electronic quality, which is promising for the development of ultrathin-body high-mobility nanoelectronics.

This Analysis illustrates how nature-positive targets aimed at protecting biodiversity can be achieved at the scale of organizations. A canteen at one UK university college is used as a case study for the application of a four-step participatory approach comprising an estimation of food-related biodiversity impacts; definition of biodiversity targets; assessment of possible interventions; and exploration of different strategies.

Owing to the fact that graphene is just one atom thick, it has been suggested that it might be possible to control its properties by subjecting it to mechanical strain. New analysis indicates not only this, but that pseudomagnetic behaviour and even zero-field quantum Hall effects could be induced in graphene under realistic amounts of strain.