Researchers have been long toiling to find materials that super conduct electricity in ambient conditions, i.e. at one or a few atmospheres of pressure and at room temperature.
Recently, the U.S. scientists have claimed to produce the first commercially accessible material named “red matter”, which has superconducting properties at room temperature.
About Red matter:
- Red matter is a mixture of Hydrogen, Nitrogen and a rare-Earth material called Lutetium.
- It is claimed to become superconductive at a temperature of just 21°C (69°F) and a pressure of 1 gigapascal. That is nearly 10,000 times the atmospheric pressure on Earth’s surface, but still far lower pressure than any previous superconducting material.
- The data reported shows a sharp drop in the electrical resistance around room temperature, the expulsion of magnetic fields, and a hump in the heat capacity (the sample expels heat from itself when cooled, as the electrons organise into the more-ordered superconducting state). However, the validity of the scientific research is still being ascertained.
Superconductors:
- Superconductors are materials that do not resist the flow of current or have zero resistance, below a fixed temperature, which is the critical temperature. E.g.,
- A portion of the electricity generated at every power plant is lost during transmission because the wires and cables that carry the current have electrical resistance.
- Once an electric current passes over a superconducting material, it can continue to flow without receiving power from any source as none of the energy involved is lost as heat.
- However, every superconductor made so far has required extraordinarily high pressures (millions of Pascal), and very low temperatures.
E.g., Aluminium becomes superconducting at temperatures less than (minus) –250° C.
Properties of Superconductors:
- Infinite conductivity with Zero resistance: When the temperature of the material is reduced below the critical temperature, its resistance suddenly reduces to zero and thus offers infinite conductivity. E.g., Mercury becomes superconductor below 4 kelvin.
- Complete expulsion of Magnetic field: Superconductors are diamagnetic i.e. oppose the magnetic field or do not allow the magnetic field lines to penetrate it. (This phenomenon is called Meisser Effect)
However, there is a certain value of the magnetic field (critical magnetic field) beyond which the superconductors lose superconductivity and convert into conductors.
Significance:
- Elimination of the loss of energy as electricity moves along the wire would mean longer-lasting batteries, more-efficient power grids and improved high-speed trains.
- Potential applications include Magnetic-energy storage systems, magnetic levitation trains, superconducting magnetic refrigerators, etc.
- Huge potential for revolutionary technologies, including efficient quantum computers, as superconductors can exhibit truly quantum phenomena.
