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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.

Moiré materials, where two van der Waals layers are stacked together with a small twist angle has proven to be a rich playground for exotic phases, with some materials, such as twisted MoTe2 being found to host quantum anomalous and fractional hall states among others. Here, An, Pan, Qiu and coauthors add to this, observing ferromagnetism in the second moiré band of twisted MoTe2.

The coupling of ferroelectricity and magnetic order enables the tunability of material properties. Here, authors realize magnetic-field-enhanced ferroelectricity and electrical-field-controlled magneto-transport in non-magnetic moiré superlattices.

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.

Recently, the quantum anomalous Hall effect has been successfully achieved in the intrinsic magnetic topological insulator MnBi₂Te₄, but zero-field quantization has proved difficult to achieve due to poor sample quality. Here, the authors report zero-field quantization and chiral edge states in five-septuple-layer MnBi₂Te₄.

Two-dimensional materials offer potential for coherent light sources but face challenges with integration in silicon photonics. Here, the authors demonstrate a high-performance on-chip photonic circuit based entirely on a van der Waals heterostructure for coherent light generation, guiding and modulation.

Graphene systems exhibit flavor order transitions driven by tuning parameters. Here, the authors demonstrate an optical technique for detecting flavor textures in graphene via the exciton response of a proximal transition metal dichalcogenide layer.

Topological polar textures in moiré ferroelectrics have been theoretically predicted but lacked experimental confirmation. Here, the authors observe alternating out-of-plane polarization in ___domain regions and vortex-like inplane polarization patterns at ___domain wall boundaries, indicative of a network of merons and antimerons.

Graphene multilayers can host heavy electrons in flat bands alongside light electrons in Dirac cones. Local probes now reveal that a finite Dirac electron population persists at the Fermi level while correlated states form in the flat bands.

Graphene was one of the first materials proposed to host the quantum spin Hall effect. However, its weak intrinsic spin-orbit interaction means that observing such an effect requires modifying the graphene band structure. Here, Ghiasi et al. combine graphene with CrPS₄ and detect quantum spin Hall states at zero magnetic field.

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.

Takashi Fujita’s discovery of RNA helicases as intracellular viral replication sensors illustrates how scientific knowledge develops in logical — and sometimes illogical — ways.

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

Atomically thin layers of a correlated topological semimetal exhibit a nonlinear Hall effect that can be used to fabricate terahertz photodetectors with a room-temperature responsivity of 0.3 A W⁻¹, a broadband terahertz range and a picosecond response time.

The authors use nitrogen-vacancy centre magnetometry to explore layer number and magnetic field evolution of ferromagnetic and antiferromagnetic domains in the A-type antiferromagnet CrPS₄.

A new study in Nature identifies a long-sought cytoplasmic 'sensor' that is responsible, at least in part, for interferon responses induced by double-stranded DNA.

Unlike typical PN junction based photovoltaic devices, bulk photovoltaic effects can exceed the Shockley-Queisser limit for efficiency, with open circuit voltages larger than the material bandgap. Here, Asada et al demonstrate a finite spontaneous photocurrent in a van der Waals heterostructure with broken P- and T-symmetry.

Synthesis of heterostructures of magnetic intercalation compounds in transition metal dichalcogenides (TMDs) via directed topotactic reactions enables the creation of multi-component magnetic architectures, overcoming limitations of crystallographic incommensurability

Observations indicating the chiral nature of superconducting states in five rhombohedral tetralayer and pentalayer graphene devices without moiré superlattice effects are reported, establishing a pure carbon material for the study of topological superconductivity.

Recent theoretical work suggested that magic-angle graphene can simultaneously host localized and itinerant electrons. Now thermoelectric measurements provide evidence of this.

Electrical transport measurements of magic-angle twisted trilayer graphene are presented.

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.

Examination of a complete structural phase diagram of twisted trilayer graphene shows that several large-scale moiré ___domain lattices can be formed, the physical properties of which can be tuned by the twist angles between layers.

The authors present electrical transport-based evidence of generalized Wigner crystal states in twisted bilayer MoSe₂ at fractional electron fillings ν = 2/5, 1/2, 3/5, 2/3, 8/9, 10/9, and 4/3, together with a Mott state at ν = 1. They further demonstrate continuous quantum melting transitions in a multi-parameter space of electron density, displacement and magnetic fields.

Evidence is shown for a skyrmion-like texture in the layer polarization of the electronic wavefunctions of a twisted two-dimensional material. This provides support for theories that link this spatial texture to the topological properties.

Designing large-scale crossbar arrays for energy efficient neuromorphic computing systems remains a challenge. Here, the authors propose Van der Waals (h-BN/graphene/h-BN) self-selective memory design able to combine, in the same cell, non-volatile and volatile behaviors with negligible sneak current.

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.

The mechanisms behind the superconducting phase in magic-angle twisted bilayer graphene (MATBG) remain debated. Here, the authors investigate radio frequency-biased Josephson junctions in MATBG, providing insights into the electron-phonon coupling and superfluid stiffness of correlated electrons.

The superconductivity in Bernal bilayer graphene that emerges from the spin–orbit coupling induced by proximal tungsten diselenide can be tuned by modulating the twist angle between the two materials.

Introducing spin–orbit coupling by substrate proximity effect leads to an enhancement of superconducting phases in rhombohedral trilayer graphene.

A class of moiré quasiperiodic crystals with unexpected electronic properties is presented, exhibiting flat bands and correlation-induced gaps that signal the emergence of correlated quantum states.

A homojunction device made from two-dimensional tungsten diselenide can be used to create circuits that exhibit multifunctional logic and neuromorphic capabilities with simpler designs than conventional silicon-based systems.

The authors observe out-of-plane ferroelectric polarization induced by interlayer sliding in a multiferroic van der Waals semiconductor. The switching voltage scales down to 0.3 V at room temperature, which promises low-power device applications.

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.

The topological properties of twisted bilayer MoTe₂ are thought to stem from a spatial texture in the layer polarization of the electronic wavefunctions. This polarization is now measured using scanning tunnelling microscopy.

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.

Nonlinear optical processes like higher-order harmonic generation in solids depend on several factors. Here the authors explore the optical nonlinearity of hexagonal boron nitride and find that enhanced nonlinearity is due to electron-phonon and phonon-polariton couplings.

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.