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Superconductor. Superconductors are materials which have the property of superconductivity. Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring when cooled below a characteristic critical temperature.
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Superconductor Superconductors are materials which have the property of superconductivity. Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring when cooled below a characteristic critical temperature. Superconductivity is in fact a special case of Superfluidity respect to electron pairs
History April 8, 1911. Heike KamerlinghOnnes first discovered superconductivity. At the temperature of 4.2 K, he observed that the resistance abruptly disappeared. During 1950s. Various theoretical explanations was built one after another including Ginzburg-Landau theory (1950) and the microscopic BCS theory (1957). In 1954. Dudley Allen Buck invented the cryotron. This is the first application of superconductivity.
Application Superconductors are used in MRI/NMR machines, mass spectrometers, and the beam-steering magnets. More recently, superconductors have been used to make digital circuits
Recent research To figure out the origin of high-temperature superconductivity, the team of scientists was led by Mathieu Le Tacon and Bernhard Keimer from the Max-Planck-Institute for Solid State Research in Stuttgart (Germany) studied the atomic vibrations as the material was cooled down below its critical temperature. They observed electron-photon coupling by far the biggest ever in a superconductor which occurs in a very narrow region of phonon wavelengths and at a very low energy of vibration of the atoms. They concluded that two electrons can’t bind themselves together into a Cooper pair because the electron-phonon coupling is in such a narrow wavelength region. this image shows the result of diffuse scattering on the high-temperature superconductor. The colored areas enable to identify the wavelength of the phonons where the coupling with the electrons is taking place.