A novel method for calculating of microwave surface resistance and magnetic levitation force of high temperature superconductors

Superconductivity can be defined as abrupt disappearance of electrical resistance of particular materials, accompanied by expelling the internal magnetic field from the sample. Since the discovery of superconductivity by Onnes in 1911, studies focusing on understanding this phenomenon and investigating new superconducting materials have continually given rise to new developments. Although the number and diversity of materials exhibiting superconductivity has increased with time, the number of those which has been utilized in practical and commercial applications has been relatively small. Following the discovery of high-temperature superconductivity, scientists have paid enormous attention on applications of superconductivity. Such applications may involve DC magnetic fields or sometimes AC currents, or both. While the losses due to the field or current can be important in such applications, in some applications, however, how interaction takes place and its magnitude may be important. Experimental studies for all of the above-mentioned applications require both time and high costs. Thus, to reduce costs, it is significantly important to conduct theoretical analyses that can solve a given problem as close to reality as possible in order to develop simple software and models, which can be effectively utilized. In this thesis, microwave surface resistance and magnetic levitation forces of type-II superconductors are investigated in detail through analyses based on the Finite-Element Method (FEM). Moreover, measurements carried out to determine the magnetic levitation force are theoretically analyzed by the developed model. From the obtained results it is concluded that the developed method can be used in theoretical analyses of both microwave surface resistance and magnetic levitation force of superconductors, which are parameters of special importance.