Generic Superconducting Inhomogeneity in Single Crystal Fe(Te$_{1-x}$Se$_{x})$ Probed by Nanostructure-transport

We have investigated the nano-scale electronic properties of the iron-based unconventional superconductor Fe(Te$_{1-x}$Se$_{x})$ with optimal Se content $x=$0.5. Using the microexfoliation method and ion milling thinning, we successfully produced Fe(Te$_{1-x}$Se$_{x})$ devices with thickness varying from 90nm down to 12nm. Our transport measurements revealed a suppression of superconductivity coinciding with the loss of normal state metallicity. Through the simulation of the formation of superconducting region in nano-scale thin flakes, we show that our observation is in line with the nano-scale inhomogeneity proposed for this material; therefore it provides a more direct evidence for the nano-scale inhomogeneous superconductivity in Fe(Te$_{1-x}$Se$_{x})$.