Interaction between microwaves and vortices: Influence of heavy ion-induced defects

• Published in: Applied superconductivity Vol. 4; no. 3; pp. 143 - 149
• Main Authors: Trotel, A., Lederer, P., Lavigne, B., Chambonnet, D., Pyée, M., Costantini, J.M.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.1996; Elsevier Science
• Subjects: Applied sciences; Circuit properties; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Heavy ion; Microstrip resonator; Experimental study; Copper Oxides; Magnetic field effect; Superconducting materials; Barium Oxides; Quaternary compound; Ion irradiation; Yttrium Oxides; Radiation effect; Microwave circuit; Reliability
• ISSN: 0964-1807; 1879-1530
• DOI: 10.1016/S0964-1807(96)00020-8

We report experimental results on the external static magnetic field dependence of the kinetic inductance of YBaCuO microstrip resonators, through microwave resonance frequency measurements. We interpret our data in terms of granularity to relate the resonance frequency variations to grain-pinned vortices or grain-boundary vortices. In order to modify the pinning characteristics of the material, the YBaCuO films were irradiated with 70 MeV 63Cu ions, which are able to produce amorphous ionization tracks in this material. We have studied the influence of these columnar defects on the frequency shifts observed in the resonator. The results show that columnar defects may act as very strong pinning centers inside superconducting grains, but they have little effects on vortices trapped in intergranular regions.