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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.

While the electronic quality of graphene has significantly improved during the last two decades, charged defects inside encapsulating crystals still limit its performance. Here, the authors overcome this limitation and report the enhanced electronic quality of graphene enabled by tuneable Coulomb screening inside large-angle twisted bilayer and trilayer graphene devices, showing Landau quantization at magnetic fields down to ~5 mT.

Here, the authors show that Brown-Zak fermions in graphene-on-boron-nitride superlattices exhibit mobilities above 10⁶ cm²/V s and micrometer scale ballistic transport.

For small twist angles, electrons can resonantly tunnel between graphene layers in a van der Waals heterostructure. It is now shown that the tunnelling not only preserves energy and momentum, but also the chirality of electronic states.

The conductivity of marginally-twisted bilayer graphene is predicted to persist in presence of a bandgap-opening interlayer bias, owing to a network of 1D conductive states at domain boundaries. Here, the authors report Aharonov–Bohm oscillations up to 100 K, whereas at liquid helium temperatures another kind of oscillation appears, due to progressive population of the narrow minibands formed by the 2D network of 1D states inside the gap.

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.

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

The physics of charge transport in graphene becomes particularly interesting near the Dirac point. Here, the authors demonstrate a negative minority carrier mobility due to drag between majority and minority carriers in graphene at the charge neutrality point.

The authors study tunneling junctions in rhombohedral MoS₂ bilayers and correlate their performance with the local domain layout. They show that the switching behavior in sliding ferroelectrics is strongly dependent on the pre-existing domain structure.

Josephson junctions based on graphene exhibit tunable proximity effects. The appearance of superconducting states when changing magnetic field and carrier concentration has now been investigated—some proximity effect survives for fields above 1 T.

Crystallographic alignment of the two graphene layers in a van der Waals heterostructure leads to resonant tunnelling with the conservation of both energy and momentum.

A single electron pump made entirely from graphene that performs at frequencies up to several gigahertz is now realized.

Encapsulated few-layer InSe exhibits a remarkably high electronic quality, which is promising for the development of ultrathin-body high-mobility nanoelectronics.

An increase in electrical resistance caused by the fundamental process of electrons scattering off of each other (umklapp scattering) is observed in graphene superlattice devices. This will limit the electrical properties of such devices.

A plethora of solid-state nanodevices rely on engineering the quantization of electrons in quantum wells. Here, the authors leverage the thickness of exfoliated 2D crystals to control the quantum well dimensions in few-layer semiconductor InSe and investigate the resonance features in the tunnelling current, photoabsorption and light emission spectra.

High-quality rhombohedral graphite films are found to offer an alternative to twisted bilayer graphene as a platform for studying correlated physics in carbon materials.

Marginal twisting of 2D semiconductor crystals enables the emergence of room temperature interfacial ferroelectricity.

A Dirac plasma in high-mobility graphene shows anomalous magnetotransport and giant magnetoresistance that reaches more than 100 per cent in a low magnetic field at room temperature.

The authors present electroluminescence measurements of light-emitting devices based on van der Waals heterostructures, and observe a lower than expected threshold voltage for intralayer electroluminescence, attributed to non-radiative Auger-type recombination of interlayer excitons and resulting energy transfer.

Disorder-induced Anderson localization usually causes conducting materials to become insulating at low temperature. Graphene is a notable exception. But by increasing the carrier density in one graphene layer, a metal–insulator transition can be induced in an isolated second layer stacked above it.

Experimental control of electron-electron interactions in materials is challenging. Here, the authors control the interactions by proximity screening with gate dielectrics of nanometer thickness, revealing qualitative changes in concentration and temperature dependences, and validating their analysis using electron hydrodynamics and umklapp scattering approaches.

Placing graphene on a boron nitride substrate and accurately aligning their crystallographic axes, to form a moiré superlattice, leads to profound changes in the graphene’s electronic spectrum.

Type-II van der Waals interfaces formed by different two-dimensional materials enable robust interlayer optical transitions, regardless of common issues such as lattice constant mismatch, layer misalignment or whether the constituent compounds are direct or indirect band semiconductors.

Plasmons confined in field effect transistors were long envisioned for resonant detection of light at THz frequencies, however realization of such photodetectors has proven challenging. Here, the authors fabricate antenna-coupled graphene transistors which exhibit resonant photoresponse to incident radiation and use them to study plasmons in graphene and its moiré superlattices.

Electron-electron interactions are known to play an important role in the in-plane transport properties of graphene-based devices. Here, the authors investigate the role of electron-electron interactions on electrons tunnelling between the layers of a graphene/hBN/graphene tunnel transistor and demonstrate the emergence of a Coulomb gap at low temperatures and in quantising magnetic fields.

Hexagonal boron nitride is used extensively as an encapsulation layer or as a tunnel or insulating barrier in emerging devices. The authors study electron tunnelling through localised electronic states in hexagonal boron nitride which could be exploited for new quantum devices.

Excitonic bands in MoSe₂/WS₂ heterostructures can hybridize, resulting in a resonant enhancement of moiré superlattice effects.

Graphene’s numerous highly desirable properties mean that it has many possible applications in various technologies and devices; these are reviewed and analysed here.

Images of the second-generation Dirac cones that form when graphene is placed on hexagonal boron nitride show the potential of using superlattices to engineer the electronic band structure of van der Waals heterostructures.

The interaction between electron and nuclear spins in quantum dots is often seen as detrimental for the use of electron spin for quantum information processing. It is now shown, however, that such interaction can be used to coherently control the polarization of tens of thousands of nuclear spins, opening the way to experiments using nuclear rather than electron spin.