Search

Fractional Chern insulators have been observed in moiré MoTe₂ at zero magnetic field, but the expected zero longitudinal resistance has not been demonstrated. Now it is shown that improving device quality allows this effect to appear.

A large-twist-angle bilayer graphene platform exhibits a quantized ratio of displacement to magnetic field at Landau-level crossings, offering a route to high-resolution cryogenic magnetometry.

The interplay between magnetism, topology, and electrical polarization is a fascinating research direction in modern condensed matter physics. Here, the authors discover an intrinsic dipole Hall effect in various magnetic insulating states of twisted MoTe₂—enabling contact-free detection of topological phase transitions.

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.

The complex electronic motion in the quantum Hall regime in semiconductors has so far eluded analysis of its microscopic structure. Here, the authors use scanning gate microscopy to measure the spatial structure of transport inside a metal in this regime, opening the way for localized manipulation of the electronic states.

The anomalous Hall effect is a macroscopic manifestation of a quantum mechanical effect. Here, Uelandet al. report the observation of a high Hall conductivity in the heavy-fermion compound UCu5, a metallic system, and explain its origin in terms of geometric frustration effects.

Room-temperature nonlinear Hall effect has been observed in wafer-scale (001)-oriented SnTe thin films, enabling wireless, ultrabroadband and low-power rectification at zero electrical bias and zero magnetic field.

Quantum Hall phases in two-dimensional systems have chiral edges, along which electrons propagate in one direction without backscattering. Here, the authors use nuclear magnetic resonance to demonstrate how chiral modes establish dynamical nuclear polarization in a quantum Hall ferromagnet.

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.

In organic semiconductors, disorder-induced traps can alter the mobility of the charges and introduce noise in transport measurements. It is now shown that simple drop-casting of perfluoropolyether on top of organic single-crystals is an effective strategy for healing charge traps. This method allows the intrinsic transport properties of these materials to be recovered as well as suppressing noise in Hall effect measurements.

Future information storage technology may exploit electrical currents to write the states of ferromagnetic nanoelements via spin torque effects. Here, the authors demonstrate such behaviour promoted by exchange bias from an interfaced antiferromagnet, which may help overcome practical device limitations.

Artificial magnetic fields enable topological transport in metamaterials. Here, authors realize a programmable optomechanical metamaterial where laser-induced synthetic magnetism gives rise to chiral phonon edge states characteristic of quantum-Hall-like behavior.

A graphenep–njunction can be created by connecting electrical gates that generate electron-doped and hole-doped areas in a flake. Here, the authors use shot-noise measurements to provide microscopic evidence that edge states are uniquely mixed along the junction in the quantum Hall regime.

The temperature-dependent transverse elongation of ferrimagnetic bubbles provides experimental evidence for an evanescent skyrmion Hall effect at zero spin density.

The spins in quantum magnets couple to each other through an exchange interaction. Here, the authors show that a weak coupling between neighbouring spins called the Dzyaloshinskii–Moriya interaction can give rise to topological behaviour in the archetypal quantum magnet strontium copper borate.

Fractional quantum Hall states can be fragile, meaning that they are difficult to probe using electrical transport measurements. Now, thermal transport is shown to be a more sensitive technique for investigating these states.

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 spin Hall effect and its inverse allow conversion between charge and spin currents in both magnetic and nonmagnetic materials. Weiet al.observe an anomaly in the temperature dependence of the inverse spin Hall effect, which suggests that it can also be used as a sensor for very small magnetic moments.

Magnetically intercalated transition metal dichalcogenides provide a platform to study the interplay of magnetism, electronic band structures, and correlations. Here the authors demonstrate a nearly magnetization-free anomalous Hall effect, collinear antiferromagnetism and non-Fermi liquid behavior in V_1/3NbS₂.

MnBi₂Te₄ has an appealing combination of topological bands and magnetic ordering. While chemical doping with Sb can be used to tune these properties, it typically comes with an increase in defect density. Here, Chen, Wang, Li, Duan, and coauthors demonstrate a defect engineering approach that preserves the topological and magnetic properties of Mn(Bi_1-xSb_x)₂Te₄.

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.

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.

The fractional quantum Hall effect, occurring for rational Landau-level filling factors, is commonly observed in GaAs heterostructures. Now, unusual even-denominator fractional quantum Hall states are reported for an oxide 2D electron system.

The generation of a spin current by the anomalous Hall effect is observed by measuring the modulation in the ferromagnetic resonance linewidth of CoFeB/Cu/NiFe trilayer films.

Orbital angular momentum transfer from optical vortex beams to electronic quantum Hall states is reported in a graphene sheet, showing a robust contribution to the radial photocurrent that depends on the vorticity of light.

The anomalous Hall effect has been observed in high-quality epitaxial thin films of non-collinear antiferromagnet Mn₃Pt, and can be switched on and off using an electric field.

Interwoven magnetic and non-magnetic layers in TbTi₃Bi₄ overcome kagome frustration, producing coupled elliptical-spiral magnetic and spin-density-wave orders and a very large anomalous Hall effect driven by strong electron–magnetic field interactions.

This Review describes the concepts behind generalized quantum Hall effects that can take place without a magnetic field, and summarizes recent experimental manifestations of these phenomena in twisted two-dimensional materials and few-layer graphene.

A study of the high-field Hall coefficient in thallium- and bismuth-based single-layer cuprates demonstrates a smooth evolution of this quantity from p to 1 + p over a wide doping range.

ZrTe₅ has received significant attention for it’s non-trivial topological band structure and reports of a large anomalous Hall effect despite being a nonmagnetic material. Here, using the Kubo-Streda formula the authors investigate the origins of the unconventional Hall response of ZrTe₅ in low and high magnetic fields.

Weyl semimetals with low crystal symmetry, such as TaIrTe4, are known to host large unconventional spin-orbit torques. Here, Pandey et al combine TaIrTe4 with the van der Waals ferromagnet, Fe3GaTe2, and achieve room temperature field-free magnetization switching with an extremely low critical current density.

Strongly correlated and topological phases of matter can be often described using the tools of quantum field theory. Here the authors report the thermal Hall effect in the antiferromagnetic skyrmion lattice of MnSc₂S₄, revealing transport features that can be attributed to an emergent SU(3) gauge field.

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.

In Bi₂O₂Se thin films, the local inversion-symmetry breaking in two sectors of the [Bi₂O₂]²⁺ layer yields opposite Rashba spin polarizations, which compensate each other and give rise to the hidden Rashba effect. Hence, the films exhibit only even-integer quantum Hall states, but there is no sign of odd-integer states.

The magnetic field is an effective tool for inducing topological phase transitions. Here, the authors tune the direction and strength of the magnetic field in an ideal Dirac semimetal, Bi₄(Br_0.27I_0.73)₄, to demonstrate multiple Weyl modes.

Large-effect variants in autism remain elusive. Here, the authors use long-read sequencing to assemble phased genomes for 189 individuals, identifying pathogenic variants in TBL1XR1, MECP2, and SYNGAP1, plus nine candidate structural variants missed by short-read methods.

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

Charge-to-spin conversion allows for the generation and control of spin polarization via a charge current. Typically, this is done with non-magnetic materials with large spin-orbit interactions such as Platinum. Herein, Dai et al demonstrate an intriguing charge-to-spin mechanism, a magnetic spin Hall effect, in a van der Waals heterostructure.

By combining satellite observations with ground-based data and expert validation, this analysis demonstrates considerable misestimation of grassland extent and thereby carbon stock estimates in previous global assessments based on remote sensing.

Moiré patterns have been experimentally observed in heterostructures comprised of topological insulator films. Here, the authors propose that topological insulator-based moiré heterostructures could be a host of isolated topologically non-trivial moiré minibands for the study of the interplay between topology and correlation.

The authors report an enhancement of the superconducting onset temperature in nanometer-thin YBa₂Cu₃O₇-δ films grown on substrates with nanofaceted surfaces. They theoretically show that the enhancement is mainly driven by electronic nematicity and unidirectional charge density waves, and further suggest that the nanofacets themselves may promote these effects.

A new type of Hall effect—the layer Hall effect—is produced in a 2D antiferromagnet that does not exhibit any net magnetization.

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%.

The classification of magnets now includes altermagnets which possess opposite-spin sublattices connected by rotation and share some features with ferro- and antiferromagnets. Here the authors report the anomalous Hall effect in Mn5Si3 and interpret the results in terms of a d-wave altermagnetic phase.

Symmetry considerations can give rise to various Hall effects in solid-state platforms. Here, the authors predict a half-quantized mirror Hall effect in a strong topological insulator.

A linear Hall response in isolated systems with time reversal symmetry is forbidden by Onsager relations. Here the authors show that this restriction is lifted by interlayer hopping in twisted bilayers, leading to a linear charge Hall effect under time reversal symmetry.