Topological matter articles from across Nature Portfolio

Topological metals with topological states that are degenerate with bulk states in both energy and wave vector represent an exciting frontier for topological materials. Here, the authors theoretically develop and experimentally realise robust boundary-localised states protected by a bulk topological invariant in a gapless acoustic crystal.

Careful measurements of the zero-field quantum anomalous Hall effect find a less-precisely-quantized Hall conductivity than the integer quantum Hall effect. Here, the authors theoretically study the effects of nonlinear corrections to the Hall conductivity in both topological and trivial magnetic insulators.

The heavy-fermion superconductor UTe₂ likely exhibits spin-triplet Cooper pairing, although a singlet component is possible. Here, using magnetic penetration depth measurements, the authors find evidence consistent with chiral B_3u+iA_u spin-triplet superconductivity in UTe₂.

Topological semimetal HoPtBi exhibits anomalous AMR effect in paramagnetic state. The AMR exhibits a novel transition from a quasi-twofold to fourfold symmetry and finally forms a stable rotated fourfold symmetry as B increases. C₂ and C₄ signals with phase angle transitions dominate the novel AMR. Anisotropy of magnetic-field tunable effect induces the topological band change and leads to the phase angle transition.

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.

Machine learning looks poised to provide breakthroughs in various fields. The authors introduce a data-driven approach to identify and classify topological phases of dynamical systems, thereby disclosing efficient solutions to find novel topological lasing modes in complex systems.