Uniaxial pressure effects on the transport properties in Ba(Fe1−xCox)2As2 single crystals

Abstract

Using single crystals of the electron-doped superconductor Ba(Fe1−xCox)2As2, doping dependence of uniaxial (c-axis) pressure effects on the transport properties has been systematically examined. Optimally doped Ba(Fe0.920Co0.080)2As2 shows Tc suppression under the c-axis pressure. In under-doped Ba(Fe0.963Co0.037)2As2, in contrast, Tc is enhanced under the c-axis pressure, which is accompanied by a suppression of the resistivity-upturn near Tc. Since the c-axis pressure in our observation (<0.4GPa) is one order of magnitude smaller than the hydrostatic pressure, both superconductivity and the competing SDW order are found to be quite sensitive to the c-axis pressure.