Detection of Meissner Effect in YBCO using Giant Magnetoresistors

Superconductivity was first discovered around 1913 by Heike Kamerlingh-Onnes as a result of his systematic study of conductivity at very low temperatures using liquid Helium. He discovered that the resistance of Mercury suddenly dropped to zero at 4.2 Kelvin. Thus at 4.2K mercury makes a transition from normal conducting state to superconductive state. This temperature at which a material’s resistance suddenly drops to zero is called critical temperature denoted by Tc.[1] But this sudden drop in resistance is not the only feature of superconductivity, along with electrical properties, the magnetic properties of the material also change.