Inter-plane resistivity in single crystals Ca(Fe$_{1-x}$Co$_x$)$_2$As$_2$ with doping level variation*

CaFe$_2$As$_2$ undergoes sharp first order tetragonal-to-orthorhombic phase transition on cooling below $T_{SM}$=175 K, accompanied by stripe type antiferromagnetic ordering. The transition temperature can be suppressed to zero by application of pressure, revealing collapsed tetragonal high pressure phase, and partial superconductivity. It can also be suppressed by Co substitution of Fe. This doping suppresses structural and magnetic instabilities and induces bulk superconductivity with $T_c$ up to 17~K Ca(Fe$_{1-x}$Co$_x$)$_2$As$_2$ with $x$=2.8\% [1]. Here we report systematics of the temperature-dependent inter-plane resistivity in this Co-doped series of compounds over complete doping phase diagram.\\[4pt] [1] S. Ren S.L. Bud'ko, W.E.Straszheim, J. Soh, M.G.Kim, A.Kreyssig, A.I.Goldman and P.C.Canfield, Phys. Rev. B {\bf 85}, 224528 (2012).