Evidence of inhomogeneous superconductivity in FeTe _1-xSe _x by scotch-tape method

We have fabricated thin films of FeTe _1-xSe _x using a scotch-tape method. The superconductivities of the thin films are different from each other although these films were fabricated from the same bulk sample. The result clearly presents the inhomogeneous superconductivity in FeTe _1-xSe _x. The difference might arise from inhomogeneity due to the excess Fe concentration. The resistivity of a thin film with low excess Fe shows good superconductivity with the sharp superconducting-transition width and more isotropic superconductivity.