The superior physical and technical properties determine the application of HTS and favour their utilization in electrical or magnetic components. Except of the critical temperature Tc where the material switches
into the superconducting state for many applications the critical current density Jc (B,T) and their dependency on the temperature T and on the magnetic flux density B is the most relevant technical parameter. Although the HTS
current state-of –the –art is satisfactory in many fields of applications, R&D activities are continually striving to obtain higher Jc values at bulks, thin films and wires.