Superconductors, materials that conduct electricity with zero resistance below a critical temperature, have been known since the early twentieth century. But for decades it was believed the phenomenon was restricted to temperatures close to absolute zero. With the discovery of high-temperature superconductors in the 1980s, that idea was overthrown — even though the high temperatures in question were of the order of −140 °C. Since then, the quest for materials that superconduct at ever-higher temperatures has flourished, and in this week’s issue, Ranga Dias and his colleagues realize a long-sought milestone: a material that superconducts at room temperature. The researchers generated a photochemically transformed carbonaceous sulfur hydride system that shows superconductivity at around 15 °C. At this point, the phenomenon still requires high pressures of at least 270 gigapascals, but the team believes that chemical tuning of the system will allow superconductivity to be achieved at lower pressures.
