SUPERCONDUCTIVITY AT HIGHER TEMPERATURE
What’s in news?
Scientist break record for highest temperature superconductor.
- Scientists say they have discovered superconductivity, the ability to conduct electricity perfectly at the highest temperatures ever recorded.
- The researchers at the University of Chicago in the US studied a class of materials in which they observed superconductivity at temperatures of about minus 23 degrees Celsius a jump of about 50 degrees compared to the previous confirmed record. The results published in the journal Nature.
- In the experiment, researchers squeezed a tiny sample of the material between two tiny diamonds to exert the pressure needed, then used X-rays to probe its structure and composition.
- This represents a big step towards creating superconductivity at room temperature, though the superconductivity happened under extremely high pressure.
- By two main properties, certain kinds of materials are better at becoming superconductive as like copper wire conducts electricity better than a rubber tube.
- The material offers zero resistance to electrical current and cannot be penetrated by magnetic fields.
- Application of this superconductor: Electrical wires without diminishing currents, Extremely fast supercomputers and Efficient magnetic levitation trains.
- The material Lanthanum Superhydrides, needed to be placed under extremely high pressure, between 150 and 170 gigapascals, more than one and a half million times the pressure at sea level.
- Only under these high-pressure conditions the material exhibit superconductivity at the new record temperature.
- The material showed three of the four characteristics needed to prove superconductivity.
- It dropped its electrical resistance, decreased its critical temperature under an external magnetic field and showed a temperature change when some elements were replaced with different isotopes.
- Meissner effect, the fourth characteristic, the material expels any magnetic field, was not detected because the material is so small that this effect could not be observed.
- Previously, scientists have been only able to create superconducting materials when they are cooled to extremely cold temperatures (say minus 240 degrees Celsius).
- Since such cooling is expensive, it has limited their applications in the world at large.