Essay on Super-Conductivity Complete Essay for Class 10, Class 12 and Graduation and other classes.
The flow of electrons is called current and the materials in which the electrons flow is called a conductor. Copper, mercury, aluminum, etc are good conductor whereas glass, rubber and wood are bad conductors, or insulators. Materials that don’t conduct electricity better than copper are called semi-conductors.
In a super conductor, elections pair up to flow without resistance at chillingly low temperatures. The discovery is unusual because organic molecules usually act as electrical insulators; but injecting them with electrons effectively changes the molecules into ‘metallic’ super conductors. The first examples of the new super conductors are made from anthracite, penetrate and pentacene. Applying a magnetic field restores their restores their insulating properties, a test of a true super-conductor. The research will shed light on the origin of super-conductivity and more generally on the properties of correlated electron systems.
In a world plagued by energy crisis, the concept of super-conductivity has come about as a boon romancing. We know that conductors are medium that allow electricity to flow through them. However, due to the resistance offered by the medium the current carrying capacity of the medium is almost reduced to half its capability. It is known that temperature is a factor that contributes to this resistance, hence, if the temperature of the carrier could be lowered to absolute zero(o K or 273 C), these carriers could be made super conductive, because at this temperature they lose all resistance.
It was in the year 1911, that a Dutch physicist Heike Kimberling Ones, discovered super conductivity. While studying that variation of electrical resistance of mercury with temperature, he found that near absolute zero temperature, the resistance dropped down to a conductivity involved more than simply very high or infinite electrical conductivity. The next step towards unfolding the mystery of super conductivity took place in 1933, when W. Meisner and R. Ochsenfeld found that a super conductor placed in a magnetic field expelled the field from the interior of the conductor. Later, it was found that super conductivity needed a temperature of 4.2 K, which was the point at which helium gas liquefies. It was in 1943, that Karl Alex Muller of Zurich Laboratory decided to work on metallic oxides called ceramics. Paul C.W. Chu of Houston University found that super-conducting materials got damaged when their temperature was raised to 52 K. Hence, he replaced barium with strontium which has a smaller atomic structure and he could raise the temperature to 54 K. Later, with the use of rare earth element, temperature was raised to 98 K.
Today thallium, barium, calcium, copper oxide, bismuth, strontium, yttrium are considered as the most attractive materials for super conductivity.
