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Superinsulator
A superinsulator is a material that at low but finite temperatures does not conduct electricity, i.e. has an infinite resistance so that no electric current passes through it. The superinsulating state is the exact dual to the superconducting state and can be destroyed by increasing the temperature and applying an external magnetic field and voltage. A superinsulator was first predicted by M. C. Diamantini, P. Sodano, and C. A. Trugenberger in 1996 who found a superinsulating ground state dual to superconductivity, emerging at the insulating side of the superconductor-insulator transition in the Josephson junction array due to electric-magnetic duality. Superinsulators were independently rediscovered by T. Baturina and V. Vinokur in 2008 on the basis of duality between two different symmetry realizations of the uncertainty principle and experimentally found in titanium nitride (TiN) films. The 2008 measurements revealed giant resistance jumps interpreted as manifestations of the v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cooper Pairs
In condensed matter physics, a Cooper pair or BCS pair (Bardeen–Cooper–Schrieffer pair) is a pair of electrons (or other fermions) bound together at low temperatures in a certain manner first described in 1956 by American physicist Leon Cooper. Cooper pair Cooper showed that an arbitrarily small attraction between electrons in a metal can cause a paired state of electrons to have a lower energy than the Fermi energy, which implies that the pair is bound. In conventional superconductors, this attraction is due to the electron–phonon interaction. The Cooper pair state is responsible for superconductivity, as described in the BCS theory developed by John Bardeen, Leon Cooper, and John Schrieffer for which they shared the 1972 Nobel Prize. Although Cooper pairing is a quantum effect, the reason for the pairing can be seen from a simplified classical explanation. An electron in a metal normally behaves as a free particle. The electron is repelled from other electrons due to thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |