superconductorsmost

Superconductors are materials that exhibit zero electrical resistance when cooled below a characteristic critical temperature. This means that an electric current can flow through them indefinitely without any energy loss due to heat. The phenomenon of superconductivity was first discovered in 1911 by Dutch physicist Heike Kamerlingh Onnes. Initially, it was observed in elements like mercury at extremely low temperatures, close to absolute zero.

The critical temperature varies greatly among different superconducting materials. For conventional superconductors, these temperatures are typically very low, often requiring liquid helium for cooling. However, the discovery of high-temperature superconductors in the 1980s, often ceramic materials, significantly raised these critical temperatures, making them more accessible for practical applications. These materials can often be cooled with liquid nitrogen, which is much cheaper and easier to handle.

The unique properties of superconductors, particularly their zero resistance and their ability to expel magnetic fields (the Meissner effect), make them highly valuable for various technological advancements. Applications include powerful electromagnets used in MRI machines and particle accelerators, levitating trains, and potentially in future energy transmission grids to eliminate power loss. Research continues to explore new superconducting materials with even higher critical temperatures and to overcome challenges related to their cost, fragility, and manufacturing.