![]() Such a high transition temperature is theoretically impossible for a conventional superconductor, leading the materials to be termed high-temperature superconductors. ![]() In 1986, it was discovered that some cuprate- perovskite ceramic materials have a critical temperature above 90 K (−183 ☌). The occurrence of the Meissner effect indicates that superconductivity cannot be understood simply as the idealization of perfect conductivity in classical physics. It is characterized by the Meissner effect, the complete ejection of magnetic field lines from the interior of the superconductor during its transitions into the superconducting state. ![]() Like ferromagnetism and atomic spectral lines, superconductivity is a phenomenon which can only be explained by quantum mechanics. The superconductivity phenomenon was discovered in 1911 by Dutch physicist Heike Kamerlingh Onnes. An electric current through a loop of superconducting wire can persist indefinitely with no power source. Unlike an ordinary metallic conductor, whose resistance decreases gradually as its temperature is lowered even down to near absolute zero, a superconductor has a characteristic critical temperature below which the resistance drops abruptly to zero. Any material exhibiting these properties is a superconductor. Superconductivity is a set of physical properties observed in certain materials where electrical resistance vanishes and magnetic flux fields are expelled from the material. ![]() A high-temperature superconductor levitating above a magnet ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |