Effect of activation volume on the defect-induced anomalous electronic transport in Rb_{0.8}Fe_2Se_2

We adopted an absolute-reaction model which is considering the hole(defect)-induced charged frictionless transport to explain the unusual experiment: Two single crystalline samples of the same nominal composition Rb \(_{0.8}\) Fe \(_2\) Se \(_2\) were prepared using the self-flux technique via two different precursor routes. Although the difference in the final chemical composition falls within a narrow range, one was superconducting with a \(T_c \sim 31\) K, while the other behaves like a narrow gap semiconductor.