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

Artikel i vetenskaplig tidskrift, 2005

By feeding current into the topmost Cu2O4 layer of a mesa etched into the surface of a Bi2Sr2CaCu2O8+x (BSCCO) single crystal, we measured its superconducting critical value from a sharp upturn or break in the current-voltage characteristics of the mesa. From this, we estimate the sheet critical current density of a single Cu2O4 plane to be similar to 0.3-0.7 A/cm at 4.5 K, corresponding to the bulk current density of 2-5 MA/cm(2). These values are among the largest ever measured for BSCCO single crystals, thin films and tapes, and we argue that they represent the true intrinsic values of the material.