The Meissner result demonstrated by levitating a magnet higher than a cuprate superconductor, which can be cooled by liquid nitrogen Less than some conditions, including really small temperatures, some ceramics show high-temperature superconductivity (in superconductivity, "high temperature" means above 30 K). The main reason for this isn't comprehended, but there https://gunnermmljg.csublogs.com/46768306/everything-about-aluminium-nitride-sputtering-target-disc