Superconductors, high Josephson junction

In 1962, B. Josephson recognized the implications of the complex order parameter for the dynamics of the superconductor, and in particular when one considers a system consisting of two bulk conductors connected by a weak link." This research led to tile development of a series of weak link devices commonly called Josephson junctions. See also Josephson Tunnel-Junction. These devices hold much promise for achieving ultra high-speed computers where switching time is of the order of 1CT11 second. 

Josephson junction A type of electronic circuit capable of switching at very high speeds when operated at temperatures approaching absolute zero. Composed of two superconductors that are separated by a thin nonsuperconducting layer in which electrons can cross through the insulating barrier, it was discovered by... 

The next step in the development of high thin-film devices after the optimization of single layer films is the introduction of defects in precisely defined positions in order locally to alter the properties of the superconductor. The use of grain boundaries as Josephson junctions in SQUlDs (Superconducting Quantum Interference Devices) is an example of how defects can be utilized. 

A number of researchers have investigated the contact resistance phenomena that occur between high temperature superconductors and conventional materials [63,86-90]. Low contact resistance values are necessary for many practical applications. High contact resistance values can lead to local heating and the loss of superconductivity at the contact interface. In addition, future applications may involve the use of superconductor/ normal metal/superconductor (S-N-S) Josephson junctions, and these devices can be fabricated only with materials that exhibit low contact resistance values. 

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