Superconducting critical current of a single Cu2O4-plane in Bi2Sr2CaCu2O8+x single crystal

Abstract

By feeding current into the topmost $\mathrm{C}{\mathrm{u}}_2{\mathrm{O}}_4$-layer of a mesa etched into the surface of a $\mathrm{B}{\mathrm{i}}_2\mathrm{S}{\mathrm{r}}_2\mathrm{CaC}{\mathrm{u}}_2{\mathrm{O}}_{8+\mathrm{x}}$ (BSCCO) single crystal, we measured its superconducting critical value from a sharp upturn or break in current-voltage characteristics of the mesas. From this, we estimate the sheet critical current density of a single $\mathrm{C}{\mathrm{u}}_2{\mathrm{O}}_4$ plane to be $\sim$\ 0.3-0.7 A/cm at 4.5 K, corresponding to the bulk current density of $2-5MA/c{\mathrm{m}}^2$. These values are among the largest ever measured for BSCCO single crystals, thin films and tapes.

17 pages, 6 figures. submitted to PRB