högtemperatursuperledning

Högtemperatursuperledare, commonly referred to as high-temperature superconductors (HTS), are materials that exhibit superconductivity at temperatures significantly higher than traditional superconductors, though still well below room temperature. The critical temperature (Tc) for HTS materials is typically above the boiling point of liquid nitrogen (77 K or -196 °C), which makes them more practical for certain applications compared to earlier superconductors requiring liquid helium cooling.

The discovery of HTS in the mid-1980s revolutionized the field of superconductivity. The first class of HTS materials discovered were cuprates, which are ceramic compounds containing copper oxide layers. These materials have complex crystal structures and their superconductivity mechanism is still a subject of active research, though it is understood to be different from the conventional Bardeen-Cooper-Schrieffer (BCS) theory that explains low-temperature superconductivity. Other classes of HTS include iron-based superconductors.

While HTS have higher critical temperatures, they often have other limitations, such as brittleness, difficulty in manufacturing into long wires, and lower critical current densities compared to some conventional superconductors. Despite these challenges, HTS have found applications in areas like magnetic resonance imaging (MRI) magnets, particle accelerators, and are being explored for power transmission, magnetic levitation, and fusion reactors. Research continues to focus on discovering new HTS materials with even higher critical temperatures and improving the properties of existing ones.