Context: IISc researchers have reported superconductivity at room temperature. Their finding, now under review, will be a breakthrough if verified.
Superconductivity is a phenomenon that, so far, has been possible only at extremely low temperatures, in the range of 100°C below zero. The search for a material that exhibits superconductivity at room temperature, or at least manageable low temperatures, has been going on for decades, without success. If the claimed discovery were confirmed, it could be one of the biggest breakthroughs in physics in this century so far.
What is superconductivity?
It is a state in which a material shows absolutely zero electrical resistance. While resistance is a property that restricts the flow of electricity, superconductivity allows unhindered flow.
In a superconducting state, the material offers no resistance at all. All the electrons align themselves in a particular direction, and move without any obstruction in a “coherent” manner.
Because of zero resistance, superconducting materials can save huge amounts of energy, and be used to make highly efficient electrical appliances.
Two fundamental properties of a superconductor:
- Zero resistance to electrical current.
Diamagnetism is a property opposite to normal magnetism that we are used to. A diamagnetic substance repels an external magnetic field, in sharp contrast to normal magnetism, or ferromagnetism, under which a substance is attracted by an external magnetic field.
How rare is this?
The problem is that superconductivity, ever since it was first discovered in 1911, has only been observed at very low temperatures, somewhere close to what is called absolute zero (0°K or -273.15°C). In recent years, scientists have been able to find superconductive materials at temperatures that are higher than absolute zero but, in most cases, these temperatures are still below -100°C and the pressures required are extreme. Creating such extreme conditions of temperature and pressure is a difficult task.
Therefore, the applications of superconducting materials have remained limited as of now.
Sources: Indian express.