Superconductors Under Pressure

A recent report claims to have shown that pressurized H2S superconducts at 190K. If confirmed, this finding will knock cuprates from their position as the highest temperature superconductors (164K), and provide a step forward towards a room-temperature superconductor. High critical temperatures are thought to be associated with unconventional superconductivity, whose physical mechanisms are yet unknown. But Ion Errea at Donostia International Physics Center, Spain, and colleagues have now shown that this assumption is incorrect for H2S at high pressures. Their theoretical calculations suggest that H2S behaves much like a conventional superconductor, where superconductivity is driven by a phonon-mediated pairing mechanism.