In collaboration with Stefan Eccles
Abstract: Superconductivity is the phenomena of a material to have an electrical resistance of zero when cooled to a certain temperature known as the critical temperature. The phenomenon of superconductivity was first observed in 1911 by Heike Kamerlingh Onnes when cooling mercury down to a temperature of 4.2 K. Since then, many advances in the field of superconductivity have been made. In 1986, superconductivity was observed at temperatures well above 30 K, which was thought to be forbidden by BCS theory. This discovery led to the classification of Type I and Type II superconductors. The former are superconducting at low temperatures and have a very shallow London penetration depth and sharp critical magnetic field. The critical magnetic field is the external field at which the superconductor no longer repels the external field. Type II superconductors have high critical temperatures and contain flux tubes, which allow for a higher critical magnetic field. The discovery of type II superconductors has had many applications in the field of science, including MRIs and particle accelerators. In lab YBa2Cu3O7, a type II superconductor, was fabricated. A powder x-ray diffraction was carried out on the sample to verify the chemical makeup and identify any impurities. Two thin rods of the sample were also used to measure the resistivity verses temperature and the Meissner effect. Procedure: To begin, a 2 gram sample of YBa2Cu3O7 was fabricated. This involved mixing, mortaring, and sintering of Y2O3, BaCO3, and CuO powders. Prior to mixing the powders, the correct stoichiometric composition was determined. This was done by relating the molar masses and molar compositions of the three powders and the desired product, YBa2Cu3O7. Below are the calculations required for fabrication of YBa2Cu3O7.Y2O3 = 225.82 g/mol BaCO3 = 197.33 g/mol CuO = 79.55 g/mol YBa2Cu3O7 =...
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