ABSTRACT
The tendency in high-critical temperature (Tc) superconductivity nowadays is toward new superconductive systems and their applications. Superconductivity up to 90–100 K was reported for Sr-Cu-O compounds synthesized under high pressures. The common features of the high-temperature superconductors are their parent compounds being antiferromagnetic (AF) insulators, consisting of layered structure based on a perovskite lattice with CuO2-square planes. Proper doping of an AF insulating compound, without CuO2-planes, may induce superconductivity. High-temperature superconductivity has allowed many opportunities for the realization of practical applications working in a more realistic manner determined by the coolant used. In addition, the better and deeper understanding of “intimate” superconductivity mechanisms and the overall theory around them, including the effect of crystal structure/doping, may encourage the creation of new materials with considerably higher Tc, enhancing also the structural stability and the short coherence length. When this dream Tc increase and how close to the room temperature is going to be materialized is the future perspective of high-Tc superconductivity.
