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Using a system to adjust the strength of cavity vacuum fields penetrating a Hall bar, a study describes the effect of the vacuum field of a cavity on electronic correlations in quantum Hall systems.

Dirac fermions at ap–njunction can exhibit a wide variety of unusual properties. Here, the authors investigate the dynamics of such fermions in a graphene junction using shot noise measurements and demonstrate the crucial role of junction length.

Whilst superlattices containing thin films of 5d transition metal oxides are expected to yield strong interfacial coupling, only weak effects have been observed. Here, the authors report strong coupling between 3d SrMnO₃ and 5d SrIrO₃due to the interplay of strong Coulomb and spin orbit interactions.

Previous models explain solid-solution strengthening by differences in atomic volume and electronegativity of the constituent atoms. Here, the authors consider both factors simultaneously and identify atomic volume as the dominant factor for FCC alloys.

Magnetization reversal in magnetic topological insulators drives quantum phase transitions between quantum anomalous Hall, axion insulator, and normal insulator states. Using novel analysis protocol, the authors investigate critical behaviours of these transitions and establish their electronic origin.

The electronic ground state of a correlated oxide interface is reversibly switched by light. Stemming from interfacial reconstructions, electrostatic confinement and photodoping, this effect opens a path towards engineering the optical response of oxides.

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.

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.

Fractional quantum Hall states in 2D electron gases arise due to strong electron-electron interactions, which makes a general theoretical understanding difficult. Fu et al. present data showing the ν = 5/3 quantum Hall state has a 3/2 plateau in the diagonal resistance that has not been captured by existing models.

Skyrmions, when driven by any applied force, experience an addition sideways motion known as the skyrmion hall effect. Here, Brearton et al. present a reciprocal space method for determining the strength of the skyrmion hall effect, making measurement possible for skyrmion lattices.

The boundaries of fractional quantum Hall states can host multiple, interacting one-dimensional edge modes, which test our understanding of strongly interacting systems. Here the authors observe the edge-mode equilibration transition that was predicted for the ν=2/3 fractional quantum Hall state.

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 current known two-dimensional topological insulators with small band gaps limit the potential for room temperature applications. Here, Chen et al. observe a sizable gap of 129 meV in a 1T'-WSe₂ single layer grown on bilayer graphene with in-gap edge state near the layer boundary.

The author demonstrates that laser-driven ultracold Fermi gases can exhibit color-orbit-like coupling with SU(3) symmetry. This leads to color-like oscillations and other quantum-chromodyamics-like phenomena in an atomic physics laboratory.

The authors demonstrate quantum Hall effect in semiconducting layered oxide Bi₂O₂Se. Its unique low mass among the oxides of 0.14 m_e and pronounced layered structure makes Bi₂O₂Se highly susceptible to the quantum confinement effects.

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.

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 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.

Non-local transport measurements on mercury telluride quantum wells show clear signatures of the ballistic spin Hall effect. The ballistic nature of the experiment allows the observed effect to be interpreted as a direct consequence of the band structure of these semiconductor nanostructures, rather that being caused by impurity scattering.

Ohmic contacts to n-type molybdenum disulfide can be created over a temperature range from millikelvins to 300 K using a window-contacted technique, which leads to evidence for fractional quantum Hall states at filling fractions of 4/5 and 2/5 in the lowest Landau levels of bilayer molybdenum disulfide devices.

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 topological Hall effect is observed at above room temperature in a bilayer heterostructure composed of thulium iron garnet and platinum, suggesting the formation of skyrmions in a magnetic insulator through the interfacial Dzyaloshinskii–Moriya interaction.

The quantum Hall effect takes place in a two-dimensional electron gas under a strong magnetic field and involves current flow along the edges of the sample. In the fractional regime, counter-propagating modes that carry energy but not charge — the so-called neutral modes — have been predicted but never observed. These authors report the first direct observation of these elusive modes.

The transport behaviour of counter-propagating edge modes in the hole-conjugate fractional quantum Hall state is not fully understood. Here, by combining local noise thermometry and thermal conductance measurements, the authors show the absence of thermal equilibration on the edge at macroscopic distances.

A unified realization of the volt, ohm and ampere can be achieved by integrating a quantum anomalous Hall resistor and a programmable Josephson voltage standard in a single cryostat.

In quantum anomalous Hall (QAH) materials, the mesoscopic scattering length (L_s) plays an instrumental role in determining transport properties. Here, the authors examine L_s in three regimes (QAH, quantum critical, and insulating) with distinct transport behaviours, and find a universal L_s across all regimes.

The nature of the fractional quantum Hall state when the lowest Landau level is half-filled remains controversial. Now, the observation of a topological phase transition at related filling fractions suggests that the half-filled state is non-Abelian.

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

This work reveals the presence of the photonic Hall effect and photonic magnetoresistance in a field-dependent random laser. This observation visualizes the influence of magnetic field on random lasers scattering at the microscopic level.

Noncoplanar magnets are promising for spintronics but are rare and challenging to find. Here, the authors provide a chemical design strategy to produce materials with noncoplanar magnetic orders, and strong signatures of their magnetism in the Hall effect.

The knowledge of quantum numbers of the edge modes is essential for understanding fractional Hall states containing counter-propagating downstream and upstream modes. Here the authors identify the edge quantum numbers by probing a crossover from non-equilibrated to equilibrated edge mode regime in thermal conductance.

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.

Recently graphene has emerged as a new platform for the study of quantum Hall states. Here, by means of noise measurements, the authors report evidence for the existence of the upstream mode and its ballistic nature in the hole-conjugate fractional quantum Hall state in a bilayer graphene device.

The intrinsic robustness to perturbations makes antiferromagnets ideal building blocks for spintronic devices, however, it also manipulation and detection of antiferromagnetic ordering difficult. Here, Xu et al demonstrate an anisotropic tunnelling magnetoresistance in an all-antiferromagnetic tunnel junction.

Hall resistance quantization measurements in the quantum anomalous Hall effect regime on a device based on the magnetic topological insulator V-doped (Bi,Sb)₂Te₃ show that the system can provide a zero external magnetic field quantum standard of resistance.

Whether paternal pre-conceptual SARS-CoV-2 infection impacts sperm RNA content, or effects offspring phenotypes, has not been previously investigated. Here authors report changes in sperm noncoding RNAs in SARS-CoV-2 infected sires and increased anxiety-like behaviors in offspring.

The quantum Hall effect in GaAs-based devices defines resistance standards accurate to within one part in 10⁻⁹ at magnetic fields close to 10 T. Here, Lafont et al. demonstrate such accuracies over an extended magnetic field range at 1.4 K in chemically vapour-deposited graphene on silicon carbide.

Material implementation of machine learning algorithms for advanced computing at cryogenic temperature remains rare. Here, the authors report a cryogenic in-memory computing platform using chiral edge states of magnetic topological insulators.

Exchange bias occurs in a variety of magnetic materials and heterostructures. The quintessential example occurs in antiferromagnetic/ferromagnetic heterostructures and has been employed extensively in magnetic memory devices. Here, via a specific field training protocol, the authors demonstrate an exchange bias of up to 400mT in odd layered MnBi2Te4.

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

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.

Kondo systems offer a rich platform to study the interplay between strong correlations and topology. Here the authors observe a large anomalous Hall conductivity in a Kondo ferromagnet USbTe, which they attribute to the Berry curvature originating from flat bands induced by the Kondo hybridization.

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.

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.

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