|
||||||||||||||||||
Localized superconductivity of twin metal crystalsa P.L. Kapitza Institute for Physical Problems, Russian Academy of Sciences, ul. Kosygina 2, Moscow, 117334, Russian Federation The new phenomenon of twinning plane superconductivity is reviewed. It has already been observed in several metals. The superconductivity is localized near a twinning plane and it appears at a temperature higher than the critical temperature of the superconducting transition of a bulk metal. The phase diagram for the twinning-plane superconductivity, plotted using the magnetic field and temperature as the coordinates, is very different for type I and type II superconductors. A detailed analysis of the experimental data on the twinning-plane superconductivity is accompanied by a theoretical description of the phenomenon. The presence of a dense twinned structure may increase considerably the critical temperature: for example, in the case of tin it has been possible to increase this temperature more than threefold. We shall discuss also the data showing that the twinning-plane superconductivity can play an important role in the recently discovered high-temperature superconductors.
|
||||||||||||||||||
|