Towards room-temperature superconductivity

Although materials with no electrical resistance at low temperatures were discovered over a century ago, it was not until such superconducting behaviour was seen above the boiling point of liquid nitrogen—which facilitated many applications—that the prospect of room-temperature superconductors seemed plausible. In recent years, the quest for higher-temperature superconductors has turned to subjecting hydrogen-based compounds to extreme pressures. Mikhail Eremets and colleagues now show that lanthanum hydride under high pressures exhibits superconductivity at 250 K, or minus 23 °C, which is almost 50 K higher than the previous record of 203 K for sulfur hydride. Other hydrides are predicted to superconduct at even higher temperatures, and insights into hydride systems could help to guide the search for high-temperature superconductors at ambient pressures.