Introduction to Superconductivity

1. Introduction to Superconductivity
• In Kamerlingh Onnes laboratory, Leiden University 1911, superconductivity was discovered. This happen when a local high school student employed for the boring job of monitoring experiments has observed that the resistivity of Hg metal vanished abruptly at about 4K.
• Bardeen Cooper and Schrieffer in 1957 have discovered the microscopic mechanism underlying superconductivity, however, all the phenomenological models with predictive power were developed in the 30’s and 40’s.
• Due to their important interest for promising technological applications, superconductors have been studied intensively. Imagine what if it could be possible if a material which has superconductivity properties at room temperature is discovered.
• Until 1986, critical temperature (Tc) at which resistance vanishes is always less than ~ 23K.
• In 1986, Bednorz and Mueller have published a paper, subsequently recognized with the 1987 Nobel Prize, for the discovery of a new class of materials which is presently included materials with Tc of ~135K.