How LK-99, the fake superconductor, was exposed by science

The discovery of a room-temperature superconductor would be a huge breakthrough for physics and engineering, enabling lossless transmission of electricity and the development of powerful magnets, motors and sensors. That’s why the scientific community was stunned when a Korean team claimed to have achieved this feat with a material called LK-99 in July 2023. However, their claim soon turned out to be false, as several replication attempts by other researchers failed to confirm the superconducting properties of LK-99 and revealed that they were due to impurities in the samples.

The original paper by the Korean team, published in the journal Science Advances, reported that LK-99 had a critical temperature of 288 K (15 °C), well above the previous record of 203 K (-70 °C) for a hydrogen sulfide compound. They also claimed that LK-99 had a unique structure consisting of alternating layers of lithium and potassium atoms, sandwiched between carbon nanotubes. They attributed the superconductivity to the quantum confinement of electrons in the nanotubes.