The geometry of mechanical metamaterials is designed to achieve specific functions, often taking inspiration from biological structures. This Perspective article argues that disorder, commonly observed in nature but traditionally avoided in metamaterials, provides interesting and unexplored design opportunities.

Kagome materials provide great opportunities for investigating diverse quantum phenomena based on the interplay of topology, electron correlation and magnetism. This Review describes the fundamental physics and properties of contemporary kagome materials and their open questions and future research directions.

New sources of extreme-ultraviolet to hard X-ray photons have enabled a wide range of short-wavelength nonlinear optical and spectroscopic methods over the past decade, and, for the future, offer unique opportunities to probe elementary dynamics in various systems.

The superconducting diode effect, in which a nonreciprocal supercurrent is generated, enables new superconducting circuit functionalities. In this Review, we present the recent experimental results in the context of theoretical work and provide an analysis of the intertwining parameters that contribute to this effect.