Thickness dependence of electrodynamic properties of TlCaBaCuO thin films

The thickness dependence of electrodynamic properties of Tl 2Ca2Ba2Cu3Ox films has been examined after correction for geometrical effects. The surface resistance increases for very thin or thick films as is consistent with the presence of a poorly superconducting layer (phase inclusions or morphology breakdown) as was detected with magnetization measurements. The temperature dependence of surface resistance has been examined at low temperatures and fitted to a multigap model. There was reasonable agreement for moderate thickness films, suggesting why such films have been and will be excellent for applications, while the behavior of other thicknesses may be dominated by grain boundaries.