Effects of uniaxial pressure and annealing on the resistivity of Ba(Fe1−xCox)2As2 Original Research Article

Single crystals of underdoped Ba(Fe1−xCox)2As2 were detwinned by applying uniaxial pressure. The anisotropic in-plane resistivity was measured using the Montgomery method without releasing pressure. The resistivity along the a-axis shows metallic behavior down to 5 K, while the resistivity along the b-axis shows an insulator-like behavior in some temperature range. Annealing the sample radically reduces the residual resistivity for x=0, and at the same time the anisotropy becomes much smaller at low temperatures.