UPSC Express

In focus: Superconductivity at room temperature

Basic concepts

• ResistanceMaterials that conduct electricity well are called conductors. Eg: Metals.
  • Resistance is an electrical quantity that measures how the device or material reduces the electric current flow through it. The resistance is measured in units of ohms (Ω).
• SuperconductorsSuperconductors are conductors that have zero resistancee. they don’t impede electricity at all.

Superconductors at present

• All known superconductors have the zero resistance property only at extremely low temperature and/or extremely high pressure.
• Right now, the highest temperature superconductor works at a temperature of about 150 K, equal to -123 C.
• To achieve superconductivity, these materials immersed in liquid helium that boils at a temperature of 4 Kelvin i.e. -273 degree Celsius.

Challenge

• The conductors that are generally used for transporting energy are copper and aluminum wires.
• The problem with these conductors is that much of the energy that is transported is wasted because of inherent resistance in these wires.
• Thus, wires made of superconductors which have zero-resistance would revolutionize the way energy is transported as energy-loss is minimum.
• However, since superconductivity is achieved at very low temperatures, they are not being used in wires.
• Besides, at such low temperatures, metal becomes extremely brittle and cannot be made into wires.

The breakthrough: Superconductivity at room temperature

• The researchers at IISC have achieved superconductivity in silver nanoparticles embedded in a gold matrix at room temperature.
• The gold-silver nano-material used exhibited superconductivity at a temperature below 13°C which can go up to 70°C.

Significance

• The achievement of superconductivity at room temperature is a breakthrough in physics as it can reduce energy loss significantly.
• Reducing energy-loss can also be significant in achieving the Paris goal of 1.5° rise in the temperature.