A star role for stripes

New images of magnetic and charge order in copper-oxide compounds are providing important clues about the nature of high-temperature superconductors. Visual images can have a powerful impact on the viewer, and this is certainly the case when the images are atomic-scale pictures of the surface of a high-temperature copper-oxide superconductor. The unusual properties of these materials have vexed condensed-matter theorists for the last 15 years. Now a new flurry of theoretical papers has been stimulated by the latest images of a cuprate superconductor, which reveal that an applied magnetic field can induce 'stripes' of charge. The experimental results provide intriguing and important clues to the nature of these ever-surprising materials - although the theorists have still to agree on their meaning. (U.K.)