Scaling behaviour of rf surface resistance in oxygen deficient single-domain YBCO

To develop high-quality rf components for wireless telecommunications, we h ave processed single-domain YBCO of various dimensions and geometry for the device applications including high-e resonators and filters. In this devel opment, a critical parameter, the surface resistance, R-s, of single-domain YBCO has been measured in wide ranges of temperature and magnetic field. W e have found that the Pippard model can best describe the well oxygenated c rystal, indicating the high-quality of single-domain YBCO. However, such sc aling breaks down when the oxygen structural disorders are introduced into the sample. A fundamentally different scaling behaviour is observed, which is closely related to the structural defects of oxygen. We report such a be haviour and discuss the possible underlying mechanism.