Superconductivity Superconductivity Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic flux fields occurring in certain materials, called superconductors, when cooled below a characteristic critical temperature. It was discovered by Dutch physicist Heike Kamerlingh Onnes on April 8, 1911, in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. 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. The occurrence of the Meissner effect indicates that superconductivity cannot be understood simply as the idealization of
Harm Kamerlingh Onnes potters" in Museum Boijmans Van Beuningen, which was one of the first museum presentations of modern artisan ceramics in the Netherlands. Harm Kamerlingh Onnes Harm Henrick Kamerlingh Onnes (15 February 1893 – 20 May 1985 in Leiden) was a Dutch portrait painter and ceramist, who also produced designs for stamps and stained-glass windows. He is best known for the small, humorous vignettes of everyday life. Kamerlingh Onnes was born in Zoeterwoude in 1893. His father Menso Kamerlingh Onnes was a painter and member of the Hague School, who in 1911 gave his son permission to develop as an artist. He