*Superconductors* are materials that lose all electrical resistance below a certain temperature. In normal metals (blue curve), resistance decreases with decreasing temperature. However, it stays at a finite value, even at very low temperatures. In a superconductor below the so-called **transition temperature**, current flows without hindrance. ![[superconductor.excalidraw.light.svg]] Superconductivity was discovered in 1911 by Heike Kammerlingh Onnes in Leiden, The Netherlands. The explanation of the effect took a bit longer. Bardeen, Cooper and Schrieffer developed the BCS theory (named with their initials) in 1957 and were awarded the Nobel prize in 1972. Today, such materials are used today in particular in MRI scanners or scientific experiments with high magnetic fields. >[!read]- Further Reading >- [[Condensed Matter Physics]] >- [[Absolute Zero Temperature]] >[!ref]- References > - J. Bardeen, L. N. Cooper, and J. R. Schrieffer, Microscopic Theory of Superconductivity, Phys. Rev. **106**, 162 (1957). >- L. N. Cooper, Bound Electron Pairs in a Degenerate Fermi Gas, Phys. Rev. **104**, 1189 (1956). >- J. Bardeen, Theory of the Meissner Effect in Superconductors, Phys. Rev. **97**, 1724 (1955). >- F. London, On the Problem of the Molecular Theory of Superconductivity, Phys. Rev. **74**, 562 (1948).