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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.

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.

Topological materials hold great promise for dissipationless information transmission. Here, the authors create Chern insulator junctions between domains with different Chern numbers in MnBi₂Te₄ to realize the basic operation of a topological circuit.

Heterobilayers of transition metal dichalcogenides host moiré superlattices that give rise to strong electron interactions. Here, the authors study the photoluminescence from interlayer excitons in a WS₂/WSe₂ heterobilayer to reveal the onset of various correlated insulating states.

Quantum spin Hall edge states are protected by time-reversal symmetry and are expected to disappear in a strong magnetic field. Here, the authors use microwave impedance microscopy and find, surprisingly, edge conduction in mercury telluride quantum wells that survives up to 9 T with little change.

One of the fundamental questions of nanoscale spin-transport is how a spin-polarized current interacts with a ferromagnet under finite bias. So far, experimental results have remained inconclusive, but a novel technique allows direct and quantitative measurements of the spin-transfer torque in magnetic tunnel junctions and should provide a basis for understanding and modelling the phenomenon.

A dual-gated moiré superlattice device made of trilayer WSe₂/WS₂/WSe₂ enables controlling quadrupolar excitons by driving quadrupolar-to-dipolar exciton transitions via tuning the excitation intensity and doping.

Interactions between excitons and correlated electrons can lead to the formation of interesting states. Now, evidence suggests that these interactions can give rise to a Mott insulator of excitons.

Exotic states emerge from the interplay between band topology and ferromagnetism, but it remains less known in canted-antiferromagnetic phase. Here, the authors realize a canted-antiferromagnetic Chern insulator in atomically-thin MnBi₂Te₄ with electrical control of chiral-edge state transport.

The transition from an indirect to direct bandgap in transition metal dichalcogenides has been observed in samples with thicknesses ranging from 8 to 1 monolayers by angle-resolved photoemission spectroscopy.

The moiré lattice of trilayer WSe₂ and monolayer WS₂ host interlayer excitons localized at different moiré sites. Using an electric field, the authors tune the superposition between two moiré sites via hybridization with intralayer excitons in WSe₂.

Twisted heterostructures of transition metal dichalcogenides host the so-called moiré excitons, or intralayer excitons modified by the moiré potential. Here the authors show tunability of the moiré excitons and the coexisting correlated electronic states in WSe₂/WS₂ superlattices with varying WSe₂ layer thickness

Van der Waals heterostructures allow for the integration of several materials with different properties in the one heterostructure. Here, Li et al combine a quantum spin hall insulator, WTe2, with an insulating ferromagnet, Cr2Ge2Te6, in a van der Waals heterostructure, with resulting proximity-induced magnetism in the WTe2 layer leading to an anomalous Hall and Nernst effect.

Optical experiments on WSe₂/MoSe₂ heterobilayers reveal signatures of moiré trions, including interlayer emission with sharp lines and a complex charge-density dependence, features that differ markedly from those of conventional trions.

Exciton condensation has been observed in various three-dimensional (3D) materials. Now, monolayer WTe₂—a 2D topological insulator—also shows the phenomenon. Strong electronic interactions allow the excitons to form and condense at high temperature.

Stacking monolayer WS₂ on top of bilayer WSe₂ creates conditions where electrons and holes can coexist in the structure. Their Coulomb interaction allows them to form bound pairs and hence an excitonic insulator state.

Twisted bilayers of WS₂ and WSe₂ have correlated states that correspond to real-space ordering of the electrons on a length scale much longer than the moiré pattern.