Superconductors.ORG herein announces the first observation of superconductivity above zero degrees Celsius. In repeated tests a small amount of the compound (Tl4Pb)Ba2MgCu8O13+ produced diamagnetic transitions over 277 Kelvin (see examples at page top) and resistive transitions over 276K (3C, 37F). This is the first time superconductivity has been seen above the freezing point of water. As such, once a refinement method is developed, this material could be successfully deployed in climates with year-round permafrost without any need for artificial cooling.
This milestone was achieved by substituting divalent lead (Pb II) into the barium (Ba) atomic sites that hole-dope the insulating layers of the 265K superconductor discovered in October 2010. Doping with Pb instead of Ba dampens lattice vibrations and further increases planar weight disparity along the C1 axis. Planar weight disparity has been found to be a key component of high temperature superconductivity. Since a minority phase also appeared near 271K magnetic, this makes the fourth and fifth world records that have resulted from a 9223 structure (shown below left).
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