Search

Moderate disorder can induce topologically nontrivial phases. Liu et al. report the experimental observations of the competition and interplay between Thouless pumping and disorder on a 41-qubit superconducting quantum processor.

Studying out-of-equilibrium entanglement fluctuations is beyond the scope of current theories. Lim et al. present an analytical theory of fluctuations in long-time dynamics of entanglement in two classes of integrable lattice models, showing features reminiscent of universal mesoscopic fluctuations.

Bilayer graphene allows the realization of electron–hole double-quantum dots that exhibit near-perfect particle–hole symmetry, in which transport occurs via the creation and annihilation of single electron–hole pairs with opposite quantum numbers.

Understanding the interaction between spin and valley degrees of freedom in graphene-based quantum dots underpins their applications in electronics and quantum information. Here, the authors study the low-energy spectrum and resolve the spin-valley coupling in single-electron quantum dots in bilayer graphene.

Whilst different models describing the two-dimensional quantum spin Hall effect exist, very few experimental systems have been realized in which to test theory. Here, the authors present a discrete trigonal lattice model for the quantum spin Hall effect and predict its realization in Au/GaAs(111).

Kagome lattices exhibit notable rich physics, however, there has been only limited study of the influence of magnetic ordering on the electronic structure. Here, by combining angle-resolved photoemission spectroscopy and first principles calculations, Lou et al. find that the spin reorientation transition has an orbital-selective effect on the Dirac fermions of the kagome material, Fe₃Ge.

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.

Finding a classical description of a quantum state can require resource-intensive tomography protocols. It has now been shown that, for bosonic systems, tomography is extremely inefficient in general, but can be done efficiently for some useful states.

Experiments that directly probe the quantum geometric tensor in solids have not been reported. Now, the quantum metric and spin Berry curvature—dual components of the quantum geometric tensor—have been simultaneously measured in reciprocal space.

3D higher-order topological insulators (HOTIs) exhibit 1D hinge states depending on extrinsic sample details, while intrinsic features of HOTIs remain unknown. Here, K.S. Lin et al. introduce the framework of spin-resolved topology to show that helical HOTIs can realize a doubled axion insulator phase with nontrivial partial axion angles.

Although 2D topological insulators have been experimentally realized, their 1D counterparts remain difficult to investigate. Here, the authors report the observation of 0D topological states localized at the ends of the zigzag-terminated germanene nanoribbons with a width below ∼2 nm, indicating the emergence of a 1D topological insulator.

Experimental systems in which non-trivial topology is driven by spontaneous symmetry breaking are rare. Now, topological gaps resulting from two excitonic condensates have been demonstrated in a three-dimensional material.

Heusler compounds have been predicted to host topological order with other emergent properties, which yet awaits for experimental evidence. Here, Liu et al. report a direct observation of topological surface states on half-Heusler compounds LnPtBi.

The observation of the quantum spin Hall effect in graphene is hindered by weak spin–orbit coupling. Here, Beugeling et al. demonstrate how topological phases may be realized in analogous artificial HgTe nanocrystal honeycomb lattices with strong spin–orbit coupling and multi-orbital ordering.

The interplay between properties of quantum correlation and learning sample complexity in bosonic quantum systems is currently unclear. The authors prove efficient learning for broad classes of non-Gaussian bosonic quantum states, identify the precise onset of exponential hardness in tomography, and uncover fundamental constraints on creating complex entangled photon states via optical interference.

Introducing spin–orbit coupling by substrate proximity effect leads to an enhancement of superconducting phases in rhombohedral trilayer graphene.

By enhancing the spin–orbit coupling in bilayer graphene using the proximity effect in a van der Waals heterostructure, band inversion occurs and an incompressible, gapped phase is produced.

Thouless pumping is a dynamical quantum effect that results in a quantized response of a many-body system. It stems from the topological properties of the band structure that emerge under a periodic drive in the adiabatic limit. This Review addresses the robustness of topology in adiabatically driven systems exploring fundamental issues regarding the roles of interactions, disorder and higher dimensions in quantum transport.

Graphene has long been considered to be a promising host for spin qubits, however a demonstration of long spin relaxation times for a potential qubit has been lacking. Here, the authors report the electrical measurement of the single-electron spin relaxation time exceeding 200 μs in a bilayer graphene quantum dot.

Long non-coding RNAs (lncRNAs) play key roles in the immune response but their properties at the single-cell level are less well understood. Here, the authors characterize differential features of lncRNAs and protein-coding genes upon Ebola infection in macaques at single-cell resolution.

Solid-state materials have emerged as a platform for probing and manipulating topological phases of matter. This Review surveys topological materials discovery in nonmagnetic crystalline solids, focusing on the role of crystal symmetry and geometry in topological material predictions.

Superconductivity has been observed experimentally in twisted trilayer graphene. Here, the authors show theoretically that extended electron-electron Coulomb interaction induces breakdown of spin-selective valley symmetry in twisted trilayer graphene, which leads to Ising superconductivity.

The properties of bilayer graphene can be tuned by twisting the layers relative to one another. Schmidt et al.now demonstrate the twist angle dependence of magnetotransport in this material system and uncover the formation of satellite Landau fans in the small-angle regime because of superlattice formation

In the recently proposed topological crystalline insulators, the topological states result from crystalline symmetries rather than time-reversal symmetry. Xu et al. report the experimental observation of a topological crystalline insulator phase in Pb_1-xSn_xTe by spin-resolved photoemission spectroscopy.

A complete electronic band theory is presented that describes the global properties of all possible band structures and materials, and can be used to predict new topological insulators and semimetals.

A flat stanene layer can be grown on Cu (111) by MBE growth, exhibiting topological properties as revealed by a combination of ARPES, STM and DFT calculations.

Elucidating the nature of topological magnets is at quantum frontier. Here the authors report a topological charge-entropy relation in TbMn₆Sn₆ that goes beyond conventional electron behavior and points to a transport visualization of Chern gapped Dirac fermions.

A topological phase of light emerges in dynamically driven nonlinear photonic crystals.

Graphene is the archetype for realizing two-dimensional topological phases of matter. Here, the authors introduce a new topological classification connected to polarization transport, where the topological number is revealed in the spatiotemporal dispersion of the susceptibility tensor.

Traditional photonic crystals consist of periodic media with a pre-defined optical response. Here, the authors combine nanostructured back-gate insulators with a continuous layer of graphene to demonstrate an electrically tunable two-dimensional photonic crystal suitable for controlling the propagation of surface plasmon polaritons.

Managing power exhaust in fusion reactors is a key challenge, especially in compact designs for cost-effective commercial energy. This study shows how alternative divertor configurations improve exhaust control, enhance stability, absorb transients and enable independent plasma regulation.

Moire bilayers support quantum spin Hall (QSH) and quantum anomalous Hall (QAH) states, but a unified explanation is missing. Mai et al. show that by including interactions in typical models, the QSH state shifts from 1/2 to 1/4 filling and gives way to the QAH state at low temperature.

The role of electron–electron interactions in generating superconductivity in few-layer graphene remains controversial. Now, the observation of interaction-driven intervalley coherence may help to explain the Cooper pairing mechanism.

Graphene nanoribbons are potential systems for engineering topological phases of matter, but the pre-required gapped phases are difficult to find. Here, the authors show that chiral graphene nanoribbons undergo a transition from metallic to topological insulators, and then to trivial band insulators as they are narrowed down to nanometer widths.