Measurement of a Sign-Changing Two-Gap Superconducting Phase in Electron-Doped Ba(Fe_{1-x}Co_x)_2As_2 Single Crystals using Scanning Tunneling Spectroscopy

M. L. Teague, G. K. Drayna, G. P. Lockhart +4

Scanning tunneling spectroscopic studies of $Ba(F{e}_{1-x}C{o}_x{)}_{2}A{s}_2$ (x = 0.06, 0.12) single crystals reveal direct evidence for predominantly two-gap superconductivity. These gaps…