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It is difficult to observe the edge-bulk correspondence in two-dimensional electron systems, which display the quantum Hall effect. Here Li et al. follow the spatial evolution of Landau levels towards an edge of graphene by scanning tunnelling studies, revealing that the edge-bulk correspondence can be preserved.

Graphene possesses a nonlinear optical response arising from its electronic dispersion. Here, the authors measure the response of graphene to an ultrafast optical field and provide an explanation of the quantum dynamics of Dirac carriers mediating the material’s nonlinear response.

Itinerant magnetism in rhombohedral multilayer graphene shows a large excess entropy from magnetic fluctuations above its critical temperature—typically only associated with local moments—which implies the decoupling of charge and isospin degrees of freedom, and results in the isospin Pomeranchuk effect.

The presence or absence of a strange metal phase in twisted bilayer graphene has been controversial. Now, measurements over a wide range of temperature and doping give much stronger evidence for its existence.

A combination of exciton sensing and optical pump–probe spectroscopy is used to investigate the dynamics of isospin orders in MATBG with WSe₂ substrate across the entire flat band, achieving sub-picosecond resolution.

The interaction between proximal 2D materials can lead to fundamental changes in electronic properties. Here, the authors provide evidence of two distinct types of spin-orbit coupling induced in bilayer graphene through the presence of a proximal MoS₂ layer.

In metals, the Coulomb potential of charged impurities is strongly screened, but in graphene, the potential charge of a few-atom cluster of cobalt can extend up to 10 nm. By measuring differences in the way electron-like and hole-like Dirac fermions are scattered from this potential, the intrinsic dielectric constant of graphene can be determined.

Relativistic Dirac fermions can be locally confined in nanoscale graphene quantum dots using electrostatic gating, and directly imaged using scanning tunnelling microscopy before escaping via Klein tunnelling.

In analogy to fluids, electric currents can exhibit viscosity — albeit with effects difficult to observe experimentally. Now, vorticity is reported as a signature feature of electron viscosity in graphene, which leads to negative nonlocal resistance.

Bernal-stacked bilayer graphene (BLG) has been extensively studied due to its tunable band gap and emerging electronic properties, but its low-energy band structure remains debated. Here, the authors report magnetotransport measurements of Bernal BLG, showing evidence of four Dirac cones and electrically induced topological transitions.

Tuning the electronic interactions by changing the dielectric environment of twisted bilayer graphene reveals the disappearance of the insulating states and their replacement by superconducting phases, suggesting a competition between the two phases.

Experimental demonstrations of materials supporting electron fluids have been elusive so far. Here, the authors investigate nonlocal transport in bilayer graphene across the ballistic-to-hydrodynamic crossover, and identify a sharp maximum of negative resistance at the transition between the two regimes.

Two closely spaced two-dimensional systems can remain strongly coupled by electron–electron interactions even though they cannot physically exchange particles. Coulomb drag is a manifestation of this interaction—in which an electric current passed through one layer causes frictional charge flow in the other—now experimentally observed in bilayer graphene

Artificial atoms, quantum systems with atom-like energy structure, have been studied with frequency spectroscopic techniques. However, much information about the energy level spectrum has been hidden, as the technique is impractical for high frequencies. A complementary technique has been developed where the energy level of an artificial atom is not scanned by tuning frequency, but amplitude of the radiation, while the frequency is tuned to a specific feature in the spectrum.