Electron microscopy of transition-metal doped BiCaSrCuO superconductors.

摘要

Superconductivity was discovered in 1911 when H. K. Onnes found no electrical resistance in Hg cooled to 4.1 K. Over one thousand additional ''low temperature'' superconductors were discovered prior to Bednorz and Muller's discovery of ''high temperature'' (40 K) superconductivity in BaLaCuO compounds in March of 1986. This discovery generated much scientific interest in oxide superconductors. Less than one year later the now well known YBaCuO class of superconductors raised the highest known superconducting transition temperature to 90 K, well above the boiling temperature of liquid nitrogen. In the following year, the highest recorded transition temperature was raised to 105 K by the BiCaSrCuO system. This system extended obtainable values of not only transition temperature, but also critical magnetic field, and critical current. This paper reviews the technology of superconductivity. 51 refs., 20 figs.