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Bilayer graphene has been shown to host fractional quantum Hall states. Here, the authors observe the fractional quantum Hall states at quarter- and half-filled Landau levels and the alternation of anti-Pfaffian and Pfaffian phases at half fillings.

Hund’s exchange interaction energy in two-dimensional materials is challenging to extract from experiments. Now, this is achieved in rhombohedral graphene, which allows an estimate of the interactions that drive the variety of correlated states in this material.

The boundaries of fractional quantum Hall states can host multiple, interacting one-dimensional edge modes, which test our understanding of strongly interacting systems. Here the authors observe the edge-mode equilibration transition that was predicted for the ν=2/3 fractional quantum Hall state.

Previous measurements of interferometers based on quantum Hall (QH) edge channels have suggested potential electron pairing effects. Here, the authors investigate the coupling between QH edge channels in graphene Aharonov-Bohm (AB) interferometers, proposing a possible single-particle explanation for the apparent interference phase jumps and AB frequency doubling.

Our understanding of the phase diagram of twisted graphene structures is incomplete. Now, twisted trilayer graphene is examined using a technique that locally images quantum oscillations and shows that a nematic semimetal is favoured at low density.

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.

The relationship between the integer and fractional quantum Hall states are of fundamental importance in condensed matter physics. Here, the authors report a universality of phase transitions in both regimes in ultraclean trilayer graphene samples.

Electrostatically tunable graphene-based electronic interferometers show non-trivial exchange statistics of quasiparticles, revealing their wave-like properties.

We measure efficient heat conductance through the electrically insulating quantum Hall bulk and propose a theoretical model based on the role played by the localized states.

Measurements of the thermal Hall conductance in the first excited Landau level of the quantum Hall effect show the existence of a state with non-Abelian excitations.

Helical modes are induced in a high-mobility two-dimensional electron gas without strong spin–orbit coupling. This platform provides a versatile playground for investigating compounded quantum Hall edge states.

Interferometers can probe the wave-nature and exchange statistics of indistinguishable particles. Quantum Hall interferometers from graphite-encapsulated graphene heterostructures now enable the observation of the Aharonov–Bohm effect and of robust fractional quantum Hall states.

Quantum Hall liquids play host to a wide range of unusual physics. Here, the authors use an electronic Fabry-Pérot interferometer to observe modulations of a quantum Hall liquid’s area, which can offer a means to study the statistics of fractional charges.

Twisted double bilayer graphene devices show tunable spin-polarized correlated states that are sensitive to electric and magnetic fields, providing further insights into correlated states in two-dimensional moiré materials.

To design and manipulate qubits, it is necessary to engineer multidimensional non-equilibrium steady states immune to decoherence in an open system. Here the authors devise a symmetry-based framework to create such non-equilibrium steady states showing characteristics of degenerate vacua of a unitary topological system.

Here, the authors perform measurements of the interference effects of Cooper Quartets (CQ), observed in a multi-terminal graphene Josephson junction where two terminals are tied by a flux loop. By biasing the superconducting contacts, they identify a superconducting branch attributed to CQ currents, and present evidence for interference between different CQ processes.

Quantum Hall ferromagnets can host magnons, collective spin-wave excitations, which have possible uses in spin-wave based information processing. Detecting these excitations electrically can be challenging. Here, Kumar, Srivastav, Roy, Park and coauthors demonstrate a noise-based approach to detecting magnons.

Quasiparticles in strongly interacting fractional quantum Hall systems carry heat according to the same quantization of thermal conductance as for particles in non-interacting systems.

Shot noise has traditionally been used to measure the charge of quasiparticles in a variety of mesoscopic systems. However, at sufficiently low temperatures, this usual notion tends to break down for fractional quantum Hall effect states.

Recently graphene has emerged as a new platform for the study of quantum Hall states. Here, by means of noise measurements, the authors report evidence for the existence of the upstream mode and its ballistic nature in the hole-conjugate fractional quantum Hall state in a bilayer graphene device.

Energy–momentum phase-matching enables strong interactions between free electrons and light waves. As a result, the wavefunction of the electron exhibits a comb structure, which was observed using photon-induced near-field electron microscopy.

This megastudy testing different interventions finds that honesty oaths are effective and can mitigate tax evasion in an incentivized game.

The sought-after exotic two-channel Kondo effect has now been observed in quantum dots. This effect, where electrons in two electrodes are entangled with each other through their interaction with a single localized spin in a quantum dot, has so far been difficult to observe, as unlike the conventional Kondo effect, this new effect cannot be described within the conventional picture for electron behaviour of Fermi liquids.

The impulsively driven antiferromagnetic Mott insulator is a model quantum many-body system predicted to realize exotic transient phenomena, however its exploration in far-from equilibrium regimes remains experimentally challenging. Here, the authors use a combination of second harmonic optical polarimetry and coherent magnon spectroscopy to investigate the ultrafast non-equilibrium dynamics of the Mott insulator Sr₂IrO₄ and find evidence of a far-from-equilibrium critical regime where static and dynamic critical behaviour decouple and which could be present in a number of other quantum materials.

The knowledge of quantum numbers of the edge modes is essential for understanding fractional Hall states containing counter-propagating downstream and upstream modes. Here the authors identify the edge quantum numbers by probing a crossover from non-equilibrated to equilibrated edge mode regime in thermal conductance.

This work reports on the synthesis and proximity-induced superconductivity in a topological insulator-based, thin-film heterostructure towards the development of a scalable material platform that could potentially support robust quantum computing.