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ductivity started Review published the eory explaining how, at some materials can y entirely without on experimental clues al hints, John Bardeen, bert Schrieffer, all at the in Urbana, explained of electrical resistance f magnetic and thermal onductors. Superconductivity in Germanium Super conductivity in dimond and silicon In 2005, the first superconducting diamond was made by the high-pressure and high temperature method. This discovery opened up a new field of superconductivity in doped semiconductor . Th e superconductivity in boron-doped diamond was synthesized at high pressure (nearly 100,000 atmospheres) and temperature (2,500–2,800 K). Later in 2006, E. Bustarret and C. Marcenat succeeded to find that superconductivity can be induced when boron is locally introduced into silicon at concentrations above its equilibrium solubility. For sufficiently high boron doping, silicon becomes metallic. They fiound that at a higher boron concentration of several per cent, achieved by gas immersion laser doping, silicon becomes superconducting. Solving conductivity in an "impossible" material Ultraclean semiconductors are by definition unable to superconduct because at low temperatures there are too few carriers available to condense into the superconducting state. In principle, one could introduce enough charge carriers into a semiconductor, say by chemical doping. However, the necessary doping is so high that it often damages the semiconductor itself. However,in2 009, Thomas Hermannsdorfer and collaborators from the Dresden High Magnetic Field Laboratory and the Forschungzentrum Dresden-Rossendorf in Germany report superconductivity at about 0.5K in gallium-doped germanium at ambient pressure. Following diamond and silicon, germanium is the third elemental semiconductor to host superconductivity at ambient pressure. The challenge is to therefore reconstruct the crystal structure by annealing, without causing the dopants to diffuse away, float to the surface, or cluster. The researchers achieve that goal by using a specialized technique called flash-lamp annealing which employs short but intense light pulses.