Abstract
Resistivity and transport critical current density have been measured as a function of temperature for patterned YBa2Cu3O7−δ and Bi2Sr2CaCu2O8+δ superconducting thin films on single-crystal (100)-oriented MgO substrates. These granular superconducting films were prepared by the metallo-organic decomposition method. Transition temperatures Tc (ρ=0) are around 72 K for YBa2Cu3O7 and 82 K for Bi2Sr2CaCu2O8 films, both 1 μm in thickness. Critical current densities approaching 105 A/cm2 have been measured in the Bi2Sr2CaCu2O8 films at low temperatures. The critical current densities in YBa2Cu3O7 films are about 40 times lower than those in the Bi2Sr2CaCu2O8 films. It was found that near Tc the critical current density in both films is proportional to (Tc−T)2, in agreement with a superconductor–normal-metal– superconductor model developed by DeGennes [P. G. De Gennes, Rev. Mod. Phys. 36, 225 (1964)]. The reason for the much higher current density in the Bi2Sr2CaCu2O8 film is believed to be due to the stronger coupling between the superconducting grains.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.