Microwave properties of high-T-c YBa2Cu3O7-delta microstrip resonators with different surface morphologies and finite thicknesses

Abstract

Microwave properties of YBa2Cu3O7-delta (YBCO) microstrip ring resonators with finite thicknesses and different surface morphologies were investigated, The unloaded quality factor of a YBCO resonator made of thick film appeared smaller than that of a different YBCO resonator made of a less thick film, due to the smaller ratio of the film thickness to the penetration depth, The measured penetration depth appeared to increase due to surface roughness, resulting in a decrease of the ratio of film thickness to the penetration depth and an increase of the effective surface resistance, A method is introduced to calculate the intrinsic surface resistance of a high-T-c microstrip resonator with finite thickness, YBa2Cu3O7-delta (YBCO) microstrip ring resonators with their thicknesses in the order of the magnetic field penetration depth were prepared from YBCO thin films grown by laser ablation on LaAlO3 and their microwave properties were measured at temperatures above the liquid nitrogen temperature and frequencies in 8-12 GHz.