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Van der Waals heterostructures offer a platform for harnessing the spin-valley degree of freedom for information processing. Here, the authors transfer optically generated spin-valley polarization from one layer to another in a two-dimensional molybdenum diselenide–tungsten diselenide heterostructure.

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.

Twisted double bilayer graphene (tDBG) comprises two Bernal-stacked bilayer graphene sheets with a twist between them. Here, the authors report a strong anomalous Hall effect in the correlated-metal regime of tDBG, indicating time reversal symmetry breaking from orbital ferromagnetism, likely associated with valley polarization.

Charge carriers in graphene can be manipulated, e.g., collimated or focused, as in conventional optics but the efficiency of these processes remains low. Zhang et al. demonstrate interference of electrons in a novel graphene microcavity device and use it to enhance collimation efficiency of the electron flow.

The existence of interlayer excitons with strong oscillator strength in bilayer MoS₂ enables their electrical manipulation up to room temperature.

Here, the authors image twisted bilayer graphene using scanning microwave imaging microscopy, revealing structures with sizes down to 1 nm. They show that is possible by using spontaneously forming nanoscale water menisci that concentrates the microwave fields in small regions.

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.

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.

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.

Plasmonic modulators have many possible applications in optical-frequency devices. Here the authors report a 2D semiconductor nonlinear plasmonic modulator enabled through strong interaction between the surface plasmon polaritons and excitons in a monolayer semiconductor integrated on top of a metallic waveguide.

Strong magnetic interfacial coupling in van der Waals heterostructures provides a new platform for discovering novel physics and effects. Here, the authors report the formation of skyrmion lattice in the WTe₂/Fe₃GeTe₂ van der Waals heterostructure and a Dzyaloshinskii–Moriya interaction with a large energy density of 1.0 mJm⁻².

Direct visualization of moiré superlattices in van der Waals heterostructures is a needed diagnostic tool for the study of periodicity-induced electronic and optical phenomena. Here, the authors demonstrate that the moiré pattern in twisted bilayer graphene can be indirectly imaged by imaging the phonon polariton interference on the top hexagonal boron nitride encapsulation layer.

Scanning tunnelling microscopy shows that electrons in twisted bilayer graphene are strongly correlated for a wide range of density. In particular, a correlated regime appears near charge neutrality and theory suggests nematic ordering.

The emission of light from correlated excitonic complexes has been recently observed in atomically thin transition metal dichalcogenides. Here, the authors report electroluminescence generated by a pulsed gate voltage from excitons, trions, and biexcitons in monolayer WSe₂ and WS₂ encapsulated with hBN.

Here, the authors experimentally demonstrate a platform for tunable polariton refractive and meta-optics based on hexagonal boron nitride and phase change Ge₃Sb₂Te₆. This combination has the advantage of the long-lived phonon-polariton with switchable refractive index of the phase change material.

Spontaneous symmetry breaking of flat bands in twisted graphene systems may lead to anomalous Hall effect with a precursor state which has not been observed. Here, the authors probe this precursor state by observing bulk valley current and large nonlocal voltage several micrometers away from the charge current path in twisted double bilayer graphene.

High-order correlated states in atomically thin transition metal dichalcogenides may be facilitated by long-lived optically dark excitons. Here, the authors report experimentally the emergence of neutral and charged biexciton species at low light intensities in encapsulated WSe₂ monolayers.

Multi-exciton states may emerge in atomically thin transition metal dichalcogenides as a result of strong many-body interactions. Here, the authors report experimental evidence of four- and five-particle biexciton complexes in monolayer WSe₂ and their electrical control.

Owing to strong Coulomb interactions, atomically thin transition metal dichalcogenides host strongly bound excitonic complexes. Here, the authors report charge-neutral biexciton and negatively charged trion-exciton complexes in hBN encapsulated monolayer WSe₂ by employing low-temperature photoluminescence spectroscopy.

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.

Natural killer T cells (NKT cells) are thought to originate at the double-positive stage of thymopoiesis. Taniguchi and colleagues find that a subset of NKT cells also appear earlier, at the double-negative stage, and that these give rise to liver-resident NKT cells with highly potent effector function.

Direct imaging and characterization of propagating plasmons in high-quality graphene, encapsulated between two films of hexagonal boron nitride, has now been achieved together with the observation of very low plasmon damping.

In monolayer transition-metal dichalcogenides, lack of inversion symmetry results in spin-split valence and conduction bands, but the small conduction band splitting is hard to probe experimentally. Here, the authors extract a sub-band spacing energy of 0.8 meV in the conduction band of monolayer MoS₂ via quantum transport measurements.

Supramolecular heterostructures have been formed by the sequential deposition of two molecular layers with different symmetries and lattice constants — one consisting of carboxylic acid, the other of cyanuric acid and melamine — on a hexagonal boron nitride substrate. Characterization by atomic force microscopy and molecular dynamics simulations shows epitaxial arrangements between the layers.

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.

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.

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.

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.

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.

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.

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.

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 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 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.

Here, the authors introduce a cryogenic scanning probe photoelectrical sensing technique, termed exciton-resonant microwave impedance microscopy, to measure the excitonic responses in monolayer MoSe2 and identify exciton polarons and their Rydberg states.

Observation and control of spin-forbidden dark excitons is demonstrated in a hybrid heterostructure of WSe₂ monolayers and plasmonic nanocavities.

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.

Phase transitions in charge density wave materials could be useful for memory and electronic device applications. Here, the authors correlate the temperature-driven transitions in the electrical and optical properties of H-TaS₂/1T-TaS₂ heterostructures to the number of endotaxial metallic H-TaS₂ monolayers.

Graphene systems have the potential to host Wigner crystal states at zero magnetic field. Here, the authors report transport signatures consistent with Wigner crystallization in AB-stacked bilayer graphene at both zero and finite magnetic fields.