suprakonduktio

Suprakonduktio, or superconductivity, is a phenomenon observed in certain materials when cooled below a characteristic critical temperature. In this state, these materials exhibit two key properties: zero electrical resistance and the expulsion of magnetic fields, known as the Meissner effect. When a material becomes superconducting, it can conduct electricity with no energy loss, meaning an electric current can flow indefinitely without diminishing.

The discovery of superconductivity dates back to 1911 when Dutch physicist Heike Kamerlingh Onnes observed that mercury lost all electrical resistance at a temperature of around 4.2 Kelvin. Since then, superconductivity has been observed in a wide range of materials, including elements, alloys, and complex ceramic compounds. These materials are often categorized into Type I and Type II superconductors, distinguished by their response to external magnetic fields.

The theoretical explanation for conventional superconductivity was provided by the Bardeen-Cooper-Schrieffer (BCS) theory in 1957, which describes how electrons can form bound pairs, called Cooper pairs, that move through the material lattice without scattering. High-temperature superconductors, discovered in the 1980s, operate at significantly higher, though still cryogenic, temperatures and their mechanisms are still a subject of active research.

The applications of superconductivity are vast and impactful, spanning fields such as magnetic resonance imaging (MRI) in medicine, high-speed magnetic levitation trains, particle accelerators, and powerful electromagnets. Overcoming the need for extremely low temperatures remains a significant challenge for widespread adoption, driving ongoing research into materials that exhibit superconductivity at more accessible temperatures.