High-order Van Hove singularities (hoVHSs) with power-law divergences in the density-of-states are drawing current interest mainly in context of two-dimensional (2D) twisted moiré materials. Using cuprate high-Tc superconductors as an example, here the authors illustrate complications that can arise in bulk materials in defining hoVHSs and the need to extend the definition of hoVHSs to include flat-band materials.

Self-motile active matter particles form a motility-induced phase separation (MIPS) state for high density and activity. By introducing an infection that causes particles to become nonmotile, MIPS clustering can arise outside the MIPS regime and exhibits time-dependent patterning from MIPS to a wetting phase and a fragmented state.

Boundary time crystals are gaining attention due to their distinctive features like persistent oscillations at the thermodynamic limit. This work shows that the boundary time crystal phase transition can be exploited for quantum-enhanced sensitivity, which bridges many-body physics and quantum metrology and hence triggers broad interest in the condensed matter and quantum technology communities.

Coulomb Explosion imaging is a promising technique to study the ultrafast nuclear dynamics which underpin molecular photochemistry. By initiating Coulomb explosion through soft X-ray ionization, the authors are able to image ultrafast nuclear dynamics of a prototypical photoreaction.

Extending the spectral range of on-chip tunable Raman laser is challenging due to the limited Raman frequency shifts and pump tuning bandwidth. The authors combine the dispersion engineering of thin film lithium niobate with cascaded Raman lasing to realize a widely tunable laser with 335-nm spectral extension and sub-milliwatt threshold.

Polarization, or a division into mutually hostile groups, is a common feature of social systems and is studied in terms of the structural balance of semicycles in signed networks. The authors propose a computationally efficient framework for multiscale analysis of structural balance based on semiwalk approximations applicable to any simple signed network.

While Majorana excitations are often considered to be a cornerstone for proposed quantum devices, their experimental detection has proven to be a significant challenge. Here, the authors theoretically and experimentally demonstrate that the Kitaev candidate material Ag₃LiIr₂O₆ may support a Majorana-Fermi surface, which could potentially serve as a “smoking gun” for a quantum spin liquid ground state through the lens of specific heat data.

Higher-order topological phase appears as a pioneering topic, and together with the non-Hermiticity, brings broad attentions recently. The authors explore the interplay between the non-Hermiticity and hierarchical topological states in a non-reciprocal framework and show the flexible reconstruction of non-Hermitian higher-order topological states.

The emergence of large intrinsic anomalous Hall effect (AHE) is tied to the Berry curvature in magnetic topological semimetals, but other alternatives to achieve AHE are still desirable. The authors show that a half-topological semimetal state provides an alternative platform for driving AHE and exhibits a nearly isotropic negative magnetoresistance.

Driving a quantum material from trivial to non-trivial topological phase can be engineered, for instance, by an applied external field but understanding the physics of the transition can be complex. Here, the authors report a pressure-induced topological phase transition from a semiconductor to a Weyl semimetal phase in 2D Te, and investigate the underlying dynamics using a range of magneto-transport techniques.

The authors present a series of correlated insulating states of twisted bilayer graphene that is detected using an atomic force microscope tip. An additional experiment demonstrates the coupling of a mechanical oscillator to a quantum device.

The sign of switching currents in supercurrent diodes depends on their flow direction, however effective strategies to control it in single platforms with large efficiency are missing. The authors realise a supercurrent diode in superconducting weak links that is tunable both in amplitude and sign of switching current by an out of-plane magnetic field in a regime without magnetic screening.

Highly-directional hyperbolic surface plasmons are widely exploited in optoelectronic devices, but obtaining the same performance in simpler platforms over metahyperbolic surfaces has technological advantages for integration. The authors predict that RuOCl₂ monolayers exhibit low-loss hyperbolic responses across the THz to UV spectral range.