There are two types superconductivity : the one of low temperature or conventional, which generally occurs only within a few degrees of absolute zero and is well understood by theoretical physicists; and that of high temperature which, to date, we know little about.
If there was a way to create this electricity at room temperature, the world could be revolutionized, as the way energy is transported, stored and produced, even having an impact on reducing greenhouse gas emissions, which cause global warming.
Superconductivity: when was the phenomenon discovered?
On April 8, 1911, physicist Heike Kamerlingh Onnes discovered a phenomenon capable of changing everything. The discovery was made through a mercury wire and how it loses its electrical resistance when it is at a low temperature of 4.2 degrees above absolute zero (-273.15°C).
Other materials were also discovered later, such as lead and tin. In the mid 1950s, American researchers John Bardeen, Leon Cooper and John Robert Schrieffer managed to postulate a plausible explanation of superconductivity at low temperatures.
According to quantum physics, at the moment that electrons group together (Cooper pairs), they try to escape the normal barriers to become free, through a solid. Such pairing is caused by the influence of phonons, which are nothing more than a structural vibration of the atoms that form the solid.
When subjected to high temperatures, these vibrations end up being interrupted. For this reason, this group of conventional conductors only work below 40 K, and to be cooled, requires the presence of helium. This theory, also known as "BCS", was the winner of the Nobel Prize in physics in 1972.
Why is superconductivity used?
Due to the limited knowledge about how these conductors work at high temperatures, practical applications are quite limited. Those that work at low temperatures and cooled with liquid helium are used to make very powerful magnets.
An example of this is the magnet that can direct and accelerate particles. One of the largest ever produced is the Large Hadron Collider and can be found in the CERN particle physics laboratory near Geneva, Switzerland. Another example of the use of these conductors is in magnetic resonance imaging, which makes use of niobium-tin alloys, to visualize body tissues.
As the years go by and investigations are being made in this field, groups of superconductors are being discovered. One of them had been announced in 2020, and it works at an almost room temperature, of 14 ºC. was located between two diamonds, almost crushing the mixture created between carbon, sulfur and hydrogen.Related:
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