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Enhancing the carrier mobility of graphene can enable the investigation of its fundamental properties and promote device applications. Here, the authors report the fabrication of double-layer graphene devices with a quantum mobility up to 10⁷ cm²V⁻¹s⁻¹ and integer quantum Hall features at magnetic fields as low as 0.002 T.

NiPS₃ is a van der Waals material, which in the bulk is antiferromagnetic. Whether the antiferromagnetism persists down to the monolayer remains a topic of debate. Here, through magnetotransport measurements Cheon et al find that monolayer NiPS₃ exhibits two magnetic transitions, with a low temperature long-range ordered state.

This study shows that electrically switchable and non-volatile dipoles can form at the interface of graphene and α-RuCl3 when separated by an ultrathin hBN layer. The dipole switching is driven by interfacial charge transfer, is stable without continuous power, and emerges in a narrow temperature window around 30 K.

NiPS₃ is a van der Waals antiferromagnetic semiconductor where the exciton formation is strongly influenced by the magnetic ordering. Previous studies have been limited to magneto-optical approaches, but here, Lebedev, Gish and coauthors succeed in making field effect transistors that operate below the Néel temperature and observe an ultranarrow electroluminescence with a high degree of linear polarization.

Ferroelectric ordering of moiré excitons and collective photon emission emerge in WSe₂/WS₂ heterobilayers near the Mott state driven by strong dipolar interactions and a transition to symmetry-broken ferroelectric phases.

Twisted bilayer (tb) MoTe₂ is an ideal platform for investigating the fractional quantum anomalous Hall effect but issues related to air sensitivity make the study of its electronic structure experimentally challenging. As a solution, the authors prepare hBN encapsulated tb-MoTe₂ and using micro-angle resolved photoemission spectroscopy determine the band structure. Furthermore, through in-situ alkali metal deposition, they obtain evidence indicating a direct band gap.

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.

Optical control of integer and fractional Chern insulators is demonstrated by circularly polarized optical pumping in tMoTe₂.

Tunable moiré WSe₂ bilayers realize Hubbard-model physics, exhibiting antiferromagnetism, strange metals and superconducting domes, offering a controllable platform to study high-transition-temperature superconductivity.

Superlubric arrays of double-bilayer graphene enable elastically coupled switching between Bernal and rhombohedral graphene polytypes under shear forces below 1 nN with an estimated energy cost of less than 1 fJ per switching event.

Optical switching of a moiré Chern ferromagnet is demonstrated in twisted molybdenum ditelluride bilayers using continuous-wave circularly polarized light, paving the way for dissipationless spintronics and quantized Chern junction devices.

Producing isolated single-photon emitters in hexagonal boron nitride with predefined spin transitions is challenging. Oxygen annealing enables the controlled fabrication of narrowband quantum emitters with optically active spin for quantum applications.

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.

Floquet engineering is often limited by weak light–matter coupling and heating. Now it is shown that exciton-driven fields in monolayer semiconductors produce stronger, longer-lived Floquet effects and reveal hybridization linked to excitonic phases.

When two moiré patterns interfere with each other, they produce a longer-wavelength supermoiré pattern. Now, the effects of a supermoiré lattice on the band structure and transport properties of twisted trilayer graphene is investigated.

Light-emitting diodes with suppressed efficiency roll-off can be created by intercalating oxygen plasma into few-layer molybdenum disulfide and tungsten disulfide.

This study reports coherent Aharonov–Bohm interference, including statistical phase contributions, in a Fabry–Pérot interferometer at two even-denominator fractional quantum Hall states in high-mobility bilayer-graphene van der Waals heterostructures is reported.

A scanning single-electron transistor is used to probe the strain dependence of moiré and supermoiré domains. It is observed that these can be considered nearly independent of each other.

Strong correlations and topology have been seen in moiré graphene, but their optical control has not been shown yet. Now, the optical manipulation of orbital magnetism and anomalous Hall effects is demonstrated in magic-angle twisted bilayer graphene.

Mechanisms for generating spin-polarized currents may be helpful for applications. Now one such mechanism that uses the unusual Landau-level spectrum of WSe₂ under a strong magnetic field is demonstrated.

The authors showcase the capabilities of time-resolved momentum microscopy to image spin- and valley-resolved excitons in monolayer WS₂ with high energy resolution, revealing distinct long-lived, valley-polarized dark excitons that dominate at different timescales.

The interaction between correlated states and the excitonic emission coherence in van der Waals moiré systems remains largely unexplored. Here, the authors report evidence of enhanced interlayer exciton emission coherence in twisted WSe₂/MoS₂ heterobilayers, attributed to exciton-exciton and exciton-electron interactions.

Graphene is known to exhibit a magnetoresistance, however, in pristine graphene, the magnetoresistance is highly temperature sensitive. Here, by combining graphene with Fe3GeTe2, Huang et al find a strongly enhanced magnetoresistance that is temperature insensitive.

Ta₂NiSe₅ is an excitonic insulator candidate. Here, the authors rule out a dominant excitonic mechanism for this material and instead point to a coupled electronic and structural phase transition using a doping-based approach.

Scanning tunnelling microscopy is used to image pristine electrostatically defined quantum Hall edge states in graphene with high spatial resolution and demonstrate their interaction-driven restructuring.

An electron beam technique can be used to write high-resolution doping patterns in graphene and MoS₂ van der Waals heterostructures, and could allow doped circuit designs to be created.

Graphene can exhibit pronounced frictional anisotropy, which was thought to arise because of nanoscale ripples. Here, the authors provide evidence that this effect could instead be a result of adsorbates that self-assemble into a highly regular superlattice of stripes with a period of four to six nanometres.

Edge-adsorbed water dipoles act as a molecular switch, inducing ferroelectricity in graphene nanoribbons. A collective motion of molecules yields a temperature-independent effect, paving the way for future electronic, memory, and neuromorphic devices.

Spin-polarized light-emitting diodes (spin-LEDs) convert the electronic spin information to photon circular polarization, but they are usually controlled only by external magnetic fields. Here, the authors report the realization of spin-LEDs based on 2D CrI₃/hBN/WSe₂ heterostructures, showing electrical tunability of the electroluminescence helicity.

Screening by a graphite gate placed at 1 nm proximity to graphene produces transformative improvement in its electronic quality, reducing charge inhomogeneity by two orders of magnitude.

Ferromagnetic semiconductors that have the critical properties of semiconductors and ferromagnetism at room temperature have so far proven elusive. Here, by doping black phosphorus with Cobalt, Fu, Qu, Hou, Chang and coauthors induce ferromagnetism that persists up to room temperature, all while maintaining black phosphorus’ semiconducting properties.

Here, the authors report the characterization of stable few-layer PdSe₂ transistors encapsulated in hexagonal boron nitride, showing field effect mobilities up to 700 cm²/Vs at room temperature and signatures of an 8-fold spin-valley degeneracy of the magnetotransport quantum oscillations at cryogenic temperatures.

Here, the authors demonstrate the electrical tunability of the nonlinear interactions, ultrafast formation and decay dynamics of layer-hybridized excitons in a field-effect device based on natural homobilayer MoS₂.

The study shows that exciton diffusivity in semiconducting moiré superlattices can be strongly modulated by correlated electrons, revealing intriguing interactions and ushering in avenues for quantum optoelectronic technologies.

Recently, a Luttinger liquid state was reported in a moiré superlattice of bilayer tungsten ditelluride at small twist angles and temperatures of a few kelvins. Here, the authors extend this result to millikelvin temperatures, supporting the existence of the 2D anisotropic Luttinger liquid as a stable ground state.

Lacking translational symmetry, the momentum-space description of quasicrystals is distinct from that of fully crystalline materials. Now, a quasicrystal with two 2D layers links different momenta from the individual layers, allowing new excitons to form.

The authors show that bichromatic moiré superlattices formed by two mismatched moiré patterns in van der Waals semiconductor heterotrilayers stabilize quadrupolar moiré trions and enable electric-field tuning of excitonic and electronic ground states.

Conventional excitons form in the free space of semiconductors. Here, the authors demonstrate that a quantum Hall antidot can form a quantum Hall exciton with an electron and a hole situated on separate corresponding edges.

The standard topological insulator is characterized by an insulating bulk and a conducting boundary, so a three dimensional insulating bulk of a topological insulator has a conducting surface. Recently, this idea was extended to the edges of the surfaces of the three dimensional material as a new topological phase, referred to as a higher-order topological insulator. Here, the authors find evidence of such higher order topological insulator states in tungsten ditelluride using heterostructures composed of tungsten ditelluride and graphene.

The authors observe the signatures of quadrupolar excitons in a WSe₂-WS₂-WSe₂ trilayer moiré superlattice, originating from the hybridization of the WSe₂ valence moiré flatbands. They further use electrostatic gating to reveal a hybridized interlayer Mott insulator state, with holes shared between the two WSe₂ layers but laterally confined in moiré superlattices.

Exotic six- and eight-particle excitonic complexes have recently been observed in 2D semiconductors. Here, the authors uncover a stable many-body exciton in WSe₂–comprising 20 interacting quasiparticles–that emerges when strong electrostatic doping fills the Q valley.

Here, the authors demonstrate that intense laser pulses drive electrons across the full Brillouin zone in monolayer WS₂, producing quantum interferences that control high harmonic generation.

Confinement effects enable the design of intersubband polaritons (ISPs) in semiconductor quantum wells (QWs), but this type of light-matter excitations has been rarely explored in van der Waals materials. Here, the authors report the observation of hyperbolic ISPs in WO_x/WSe₂ QW heterostructures with electrically tunable dispersions.

The authors study gate-defined Josephson junctions in four-layer twisted graphene. Field-dependent measurements of the critical current show a Fraunhofer-like pattern with sudden shifts, which they attribute to vortices jumping into and out of the superconducting leads.

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.