The superconducting materials are those that, under certain conditions, have the ability to conduct electrical current without any resistance or loss of energy. For example: Mercury, Lithium, Titanium, Cadmium.
The resistance of a superconductor, unlike that of ordinary conductors like gold and silver, drops sharply to zero when the material cools below its critical temperature: an electric current flowing in a spiral of superconducting wire It can cycle indefinitely without a power supply.
Discovery of superconductivity
Superconductivity is a phenomenon linked to quantum mechanics and was discovered in 1911 by the Dutch scientist Heike Kamerlingh Onnes, who observed that the electrical resistance of mercury disappeared when it was cooled to a temperature of 4 Kelvin (-269ºC).
Superconductivity normally occurs at low temperatures, although for a conductor to function as a superconductor, it is also necessary that a critical current and magnetic field not be exceeded.
The first discovered superconductors operated at critical temperatures of around minus 250°C. In the 1980s, high-temperature superconductors were discovered, which had a critical temperature of approximately minus 179ºC. This greatly made the study of materials cheaper and also opened the door to the existence of superconductors at room temperature.
Classification of superconducting materials
If a weak external magnetic field is applied to a superconductor, it repels it. When the magnetic field is high, the material is no longer superconducting. This critical field causes a material to stop being a superconductor.
An additional classification that is made with respect to these conductors is the one that divides them according to their ability to totally shield an external magnetic field. Type I superconductors completely prevent the penetration of external magnetic fields, while type II superconductors are imperfect in the sense that they allow the magnetic field to penetrate inside them.
Uses and applications of superconducting materials
Until now, the main utility of superconductors is the production of very strong magnetic fields without loss of energy. Thus, they have applications in medicine, in the construction of particle accelerators and the control of nuclear reactors, among other things. The development of superconductors also allows progress in the study of faster computers with greater memory, high-speed magnetic levitation trains and the possibility of generating electricity more efficiently.
In addition, superconductors are used in physics laboratories for research purposes, for example, in nuclear magnetic resonance studies and high-resolution electron microscopy.
Methods for obtaining superconducting materials
Obtaining superconducting materials is subject, for the moment, to achieving extremely low temperatures, which is why elements such as helium or liquid nitrogen are usually used.
Examples of superconducting materials
Carbon (superconductor in a modified form) Cadmium Zirconium Chromium (superconductor in a modified form) Sulfur (superconductor under high pressure conditions) Uranium Lithium Selenium (superconductor under high pressure conditions) Niobium Beryllium Osmium Molybdenum Titanium Strontium (superconductor under high pressure conditions pressure) Ruthenium Vanadium Barium (superconductor under high pressure conditions) Rhodium Oxygen (superconductor under high pressure conditions) Boron (superconductor under high pressure conditions) Calcium (superconductor under high pressure conditions) Iridium Tungsten Silicon (Superconductor under high pressure conditions pressure) Technetium Tantalum Americium Rhenium Phosphorus (superconductor under high pressure conditions) Aluminum Indium Mercury Gallium Thallium Arsenic (superconductor under high pressure conditions) Tin Zinc Bromine (superconductor under high pressure conditions) Lead Bismuth