The earlier of December, 2018, Mikhail Eremets and his colleague from MARPLE Chemical Institute, Germany found the superconducting properties of lanthanum hydride(LaH10) appear at 250K or -2℃, however it needs high pressure condition as 170Gpa,which is equal to half of earth center pressure or 1 million 700 thousand times of standard atmospheric pressure.
At the same time, the researchers from George Washington University found lanthanum hydride acts superconductivity at 280K(7℃), but with the pressure 202 Gpa, which is 2 million 2 thousand times of standard atmospheric pressure. Present best superconductor need to cool less than temperature of liquid ammonia or liquid nitrogen. Superconductivity at room temperature is what scientists seek for all the time.
Superconductivity at high room temperature of lanthanum hydride is found in 2014. The samples that Germany researchers use are tiny, so there is a key index for testing superconductivity, Meissner effect , is not test yet. However the American researchers claimed they observed Meissner effect.
Other scientists is cautious about the result. Erements team’s paper is published on arXiv, American researchers published their paper on <Physical Review Letters>.