Search

The study shows a micron-scale polariton structure where an artificial gauge field creates topological, non-reciprocal edge transport without strong magnetic fields, overcoming key limits for topological polariton lasers and devices.

Herbertsmithite is a kagome material presumed to host a spin liquid phase with fractionalized excitations. Here, Mazin et al.study the crystallographic and electronic properties of gallium-substituted herbertsmithite, finding that it has symmetry-protected Dirac points at the Fermi level.

To date, experimental demonstrations of PT-symmetric systems have been restricted to one dimension. Here, the authors experimentally realize and characterize a two-dimensional PT-symmetric system using photonic lattice waveguides with judiciously designed refractive index landscape and an alternating loss distribution.

The origin of the nematic state in the kagome metal CsTi₃Bi₅ remains unclear. Here, using polarization-dependent angle-resolved photoelectron spectroscopy and ab initio based field theoretical methods, the authors propose a d-wave nematic order driven by electronic correlations via an orbital-selective mechanism.

Spaces with negative curvature are difficult to realise and investigate experimentally, but they can be emulated with synthetic matter. Here, the authors show how to do this using an electric circuit network, and present a method to characterize and verify the hyperbolic nature of the implemented model.

The strength of the interactions between electrons in a structure called twisted bilayer graphene has been tuned by adjusting the immediate environment — a major advance for tunable electronic quantum matter.

An unconventional chiral charge order is observed in a kagome superconductor by scanning tunnelling microscopy. This charge order has unusual magnetic tunability and intertwines with electronic topology.

The realization of a two-dimensional quadrupole topological insulator—featuring gapless corner states but an otherwise insulating bulk and edge—establishes electrical circuits as a versatile platform for implementing topological band structures.

The authors report that tensile strain applied to CsV₃Sb₅ strongly suppresses the charge-density-wave (CDW) gap, increases the mass of the fermions at the higher-order van Hove singularity (HO-VHS) and drives the energy of the HO-VHS towards the Fermi energy. Further, they suggest an important role of the HO-VHS in superconducting pairing.

The authors propose a non-Hermitian topological insulator with a real-valued energy spectrum based on a periodically driven Floquet model implemented in a photonic platform where generalized parity–time symmetry is protected against spontaneous symmetry breaking under a spatiotemporal gain and loss distribution.

Using normal and Josephson scanning tunnelling microscopy, chiral kagome superconductivity modulations with corresponding residual Fermi arcs are detected in KV₃Sb₅ and CsV₃Sb₅.

Quantum states are incredibly sensitive to their environment, making them perfect for ultrasensitive quantum detection—if they can be maintained long enough. Here, the authors showed that they can ‘immortalize’ the excited state of a coupled light-matter system using a technique called ‘coherent perfect absorption’.

Scanning tunnelling microscopy and scanning tunnelling spectroscopy have been used to observe intra-unit-cell nematic order and associated Fermi surface deformation in ScV₆Sn₆.

A frequency detuning between two pump lasers enables an exciton–polariton Floquet optical lattice and a polariton ‘conveyor belt’. The findings pave the way for Floquet engineering in polariton condensates.

The direct observation of spin Berry curvature, an important aspect of non-trivial band topology, has not been achieved in quantum materials. Now it is observed in a bilayer Kagome metal.

One-dimensional chains of magnetic adatoms on the surface of a superconductor have been claimed to host topological states. Now, this idea is extended to two-dimensional systems.

A topological superconductor is an exotic state of matter that is gapped in the bulk but possesses gapless surface states, but its identification has been so far elusive. Here, the authors develop a theory for scanning tunnelling microscopy which would allow to resolve topological superconductor states.

The existence of the optical Berry phase in all-dielectric Möbius-strip cavities is experimentally confirmed. In contrast to a predicted sole Berry phase value of π, arbitrary values of the Berry phase upon adiabatic evolution of a linearly or elliptically polarized light wave are obtained.

Here, the authors report the observation of room temperature excitons in a single layer of bismuth atoms epitaxially grown on a SiC substrate - a material of non-trivial global topology - with excitonic and topological physics deriving from the very same electronic structure.

Hyperbolic lattices emulate particle dynamics equivalent to those in negatively curved space, with connections to general relativity. Here, the authors use electric circuits with a novel complex-phase circuit element to simulate hyperbolic graphene with negligible boundary contributions.

Predictions suggest enhanced correlation effect due to multiple van Hove singularities (VHS) in the vicinity of the Fermi level in the recently discovered AV₃Sb₅ kagome metals. Here the authors identify three VHSs close to the Fermi level with diverse sublattice characters in CsV₃Sb₅, and one of them shows flat dispersion suggesting the higher-order nature.

Three-dimensional topological insulators have become a research focal point on topological quantum matter. Here, the authors propose the non-Hermitian analogue, the exceptional topological insulator, with anomalous surface states only existing within the topological bulk embedding.

Viscous electron fluids are predicted in strongly correlated systems but remain challenging to realize. Here, the authors predict enhanced effective Coulomb interaction and reduced ratio of the shear viscosity over entropy density in a Kagome metal, inferring turbulent flow of viscous electron fluids.

Multiple different types of topological states are observed in iron-based high-temperature superconductors. This suggests that these may be a good place to try and engineer high-temperature topological superconductivity.

Quantum spin liquids have magnetic moments that do not form magnetic order even as the temperature approaches zero, leading to the dominance of quantum fluctuations. Chillal et al. present evidence that the hyper-hyperkagome lattice of PbCuTe₂O₆ hosts a three-dimensional quantum spin liquid.

Topological phases with knotted configurations in momentum space have been challenging to realize. Here, Lee et al. provide a systematic design and measurement of a three-dimensional knotted nodal structure, and resolve its momentum space drumhead states via a topolectrical RLC-type circuit.

Rashba type spin splitting – relevant for spintronics applications - is driven by inversion symmetry breaking but could so far not be realized in all momentum directions in a crystal. Here, the authors report on PtBi₂ that exhibits Rashba spin splitting in all three momentum directions.

The discovery of topological insulators has given rise to a flourishing field dedicated to the investigation of the topological state of matter. This manuscript contributes to this field by introducing the idea of a topoelectrical circuit, whereby an assembly of conventional circuit elements realises various topological band structures.

Superconductivity and ordered states formed by interactions—both of which could be unconventional—have recently been observed in a family of kagome materials.

Kagome metals are remarkably interesting due to the strong interplay of topology, magnetism, van-Hove singularities, correlated flat bands, and structural degrees of freedom. Here, the driving mechanism and dynamics of the charge density wave phase in ScV6Sn6 are investigated by experimental and theoretical techniques, revealing a predominant role of phonons in its stabilization.

Scaling theory governs much of the physics around us. Here, the authors present experimental evidence showcasing the breakdown of logarithmic scaling in electric circuits and the emergence of fractal-like patterns in impedance scaling relationships.

Non-Hermitian systems have opened up a new level of complexity to non-trivial topological phases, particularly on the bulk-boundary correspondence in higher dimensions. Here, the authors developed a theoretical framework of tidal surface states for gapless nodal non-Hermitian metals, and explain their realizations with topolectrical circuits