| Περίληψη: | Definition of superconductivity, properties (zero resistivity, Meissner effect). Critical properties (superconducting critical temperature, Tc, critical field strength, Hc, critical current density, Jc). Temporal evolution of the critical temperature by superconductors. High temperature superconductor YBCO (structure, Tc as function of the oxygen stoichiometry). Superconductor ΜgB2 (properties). Theory BCS for superconductivity. Preparative methods for superconductors (preparation of powders, bulk and coatings/thin films). Powders and bulk devices (solid state reaction, co-precipitation from liquids, sol-gel, spray pyrolysis, explosive compression). Coatings, thin films (sputtering, laser ablation, electrophoresis, factors affecting the electrophoretic technique, requirements to the substrates, advantages). Characterization methods for superconductors. Uses and applications of superconductors. Demonstration of the lab exercise: “Preparation and characterization of high temperature superconductors and of magnesium diboride”.
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